Polycyclic compound and organic light-emitting device including the same

ABSTRACT

A polycyclic compound and an organic light-emitting device, the compound being represented by Formula 1:

CROSS-REFERENCE TO RELATED APPLICATION

Korean Patent Application No. 10-2016-0095488, filed on Jul. 27, 2016,in the Korean Intellectual Property Office, and entitled: “PolycyclicCompound and Organic Light-Emitting Device Including the Same,” isincorporated by reference herein in its entirety.

BACKGROUND 1. Field

Embodiments relate to a polycyclic compound and an organiclight-emitting device including the same.

2. Description of the Related Art

Organic light-emitting devices are self-emission devices, have wideviewing angles, high contrast ratios, short response times, andexcellent brightness, driving voltage, and response speedcharacteristics, compared to conventional devices, and producefull-color images.

An example of such organic light-emitting devices may include a firstelectrode disposed on a substrate, and a hole transport region, anemission layer, an electron transport region, and a second electrode,which are sequentially disposed on the first electrode. Holes providedfrom the first electrode may move toward the emission layer through thehole transport region, and electrons provided from the second electrodemay move toward the emission layer through the electron transportregion. Carriers, such as holes and electrons, recombine in the emissionlayer to produce excitons. These excitons transition from an excitedstate to a ground state, thereby generating light.

SUMMARY

Embodiments are directed to a polycyclic compound and an organiclight-emitting device including the same.

The embodiments may be realized by providing a polycyclic compoundrepresented by Formula 1:

wherein, in Formula 1, X₁ is C(R₁₁)(R₁₂), N(R₁₃), O or S, and R₁ to R₁₃are each independently a structure represented by Formula 2, hydrogen,deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, a substituted or unsubstituted C₁-C₆₀ alkyl group, a substitutedor unsubstituted C₂-C₆₀ alkenyl group, a substituted or unsubstitutedC₂-C₆₀ alkynyl group, a substituted or unsubstituted C₁-C₆₀ alkoxygroup, a substituted or unsubstituted C₃-C₁₀ cycloalkyl group, asubstituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, asubstituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted orunsubstituted C₁-C₁₀ heterocycloalkenyl group, a substituted orunsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₆-C₆₀aryloxy group, a substituted or unsubstituted C₆-C₆₀ arylthio group, asubstituted or unsubstituted C₁-C₆₀ heteroaryl group, a substituted orunsubstituted monovalent non-aromatic condensed polycyclic group, asubstituted or unsubstituted monovalent non-aromatic condensedheteropolycyclic group, —Si(Q₁)(Q₂)(Q₃), —N(Q₁)(Q₂), —B(Q₁)(Q₂),—C(═O)(Q₁), —S(═O)₂(Q₁), or —P(═O)(Q₁)(Q₂), at least one of R₁ to R₁₀having a structure represented by Formula 2,

wherein, in Formulae 1 and 2, L₁ is a substituted or unsubstitutedC₃-C₁₀ cycloalkylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkylene group, a substituted or unsubstituted C₃-C₁₀cycloalkenylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenylene group, a substituted or unsubstituted C₆-C₆₀arylene group, a substituted or unsubstituted C₁-C₆₀ heteroarylenegroup, a substituted or unsubstituted divalent non-aromatic condensedpolycyclic group, or a substituted or unsubstituted divalentnon-aromatic condensed heteropolycyclic group, Ar₁ is a substituted orunsubstituted C₁-C₆₀ heterocyclic group having at least one *—N═*′moiety, a1 is an integer from 1 to 5, b1 is an integer from 1 to 5, whenal is two or more, two or more L₁(s) are identical to or different fromeach other, when b1 is two or more, two or more Ar₁(s) are identical toor different from each other, Ar₂ is a substituted or unsubstitutedC₆-C₆₀ aryl group, a substituted or unsubstituted C₆-C₆₀ aryloxy group,a substituted or unsubstituted C₆-C₆₀ arylthio group, or a substitutedor unsubstituted C₁-C₆₀ heteroaryl group, and R₁₃ and Ar₂ are separateor are linked to a neighboring substituent to form a substituted orunsubstituted ring, * and *′ each indicate a binding site to aneighboring atom, and at least one substituent of the substituted C₃-C₁₀cycloalkylene group, the substituted C₁-C₁₀ heterocycloalkylene group,the substituted C₃-C₁₀ cycloalkenylene group, the substituted C₁-C₁₀heterocycloalkenylene group, the substituted C₆-C₆₀ arylene group, thesubstituted C₁-C₆₀ heteroarylene group, the substituted divalentnon-aromatic condensed polycyclic group, the divalent non-aromaticcondensed heteropolycyclic group, the substituted C₁-C₆₀ alkyl group,the substituted C₂-C₆₀ alkenyl group, the substituted C₂-C₆₀ alkynylgroup, the substituted C₁-C₆₀ alkoxy group, the substituted C₃-C₁₀cycloalkyl group, the substituted C₁-C₁₀ heterocycloalkyl group, thesubstituted C₃-C₁₀ cycloalkenyl group, the substituted C₁-C₁₀heterocycloalkenyl group, the substituted C₆-C₆₀ aryl group, thesubstituted C₆-C₆₀ aryloxy group, the substituted C₆-C₆₀ arylthio group,the substituted C₁-C₆₀ heteroaryl group, the substituted monovalentnon-aromatic condensed polycyclic group, the substituted monovalentnon-aromatic condensed heteropolycyclic group, the substituted C₁-C₆₀heterocyclic group, or the substituted ring is: deuterium, —F, —Cl, —Br,—I, a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀ alkynyl group, or a C₁-C₆₀ alkoxy group; aC₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, anda C₁-C₆₀ alkoxy group, each substituted with at least one selected fromdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₃-C₁₀cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, amonovalent non-aromatic condensed polycyclic group, a monovalentnon-aromatic condensed heteropolycyclic group, a C₁-C₆₀ heterocyclicgroup, —Si(Qii)(Q₁₂)(Q₁₃), —N(Q₁₁)(Q₁₂), —B(Q₁₁)(Q₁₂), —C(═O)(Q₁₁),—S(═O)₂(Q₁₁), or —P(═O)(Q₁₁)(Q₁₂); a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆ ⁻C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, a C₁-C₆₀ heterocyclic group, abiphenyl group, or a terphenyl group; a C₃-C₁₀ cycloalkyl group, aC₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, a C₁-C₆₀ heterocyclic group, abiphenyl group, and a terphenyl group, each substituted with at leastone selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amidino group, a hydrazino group, a hydrazonogroup, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynylgroup, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, a biphenyl group, a terphenyl group,—Si(Q₂₁)(Q₂₂)(Q₂₃), —N(Q₂₁)(Q₂₂), —B(Q₂₁)(Q₂₂), —C(═O)(Q₂₁),—S(═O)₂(Q₂₁), or —P(═O)(Q₂₁)(Q₂₂); or —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂),—B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁), —S(═O)₂(Q₃₁), or —P(═O)(Q₃₁)(Q₃₂), wherein Q₁to Q₃, Q₁₁ to Q_(13,) Q₂₁ to Q_(23,) and Q₃₁ to Q₃₃ are eachindependently hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, acyano group, a nitro group, an amidino group, a hydrazino group, ahydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, aC₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryl groupsubstituted with a C₁-C₆₀ alkyl group, a C₁-C₆₀ heteroaryl group, amonovalent non-aromatic condensed polycyclic group, a monovalentnon-aromatic condensed heteropolycyclic group, a C₁-C₆₀ heterocyclicgroup, a biphenyl group, or a terphenyl group.

The embodiments may be realized by providing an organic light-emittingdevice including a first electrode; a second electrode facing the firstelectrode; and an organic layer between the first electrode and thesecond electrode, the organic layer including an emission layer, whereinthe organic layer includes the polycyclic compound according to anembodiment.

BRIEF DESCRIPTION OF THE DRAWING

Features will be apparent to those of skill in the art by describing indetail exemplary embodiments with reference to the attached drawings inwhich:

FIG. 1 illustrates a schematic view of an organic light-emitting deviceaccording to an example embodiment.

DETAILED DESCRIPTION

Example embodiments will now be described more fully hereinafter withreference to the accompanying drawing; however, they may be embodied indifferent forms and should not be construed as limited to theembodiments set forth herein. Rather, these embodiments are provided sothat this disclosure will be thorough and complete, and will fullyconvey exemplary implementations to those skilled in the art.

In the drawing figure, the dimensions of layers and regions may beexaggerated for clarity of illustration. It will also be understood thatwhen a layer or element is referred to as being “on” another layer orelement, it can be directly on the other layer or element, orintervening layers may also be present. In addition, it will also beunderstood that when a layer is referred to as being “between” twolayers, it can be the only layer between the two layers, or one or moreintervening layers may also be present. Like reference numerals refer tolike elements throughout.

A polycyclic compound according to an embodiment may be represented byFormula 1.

X₁ in Formula 1 may be one selected from, e.g., C(R₁₁)(R₁₂), N(R₁₃), O,and S.

In one or more embodiments, X₁ may be C(R₁₁)(R₁₂).

In one or more embodiments, X_(i) may be N(R₁₃).

In one or more embodiments, X₁ may be O or S.

R₁ to R₁₃ in Formula 1 may each independently be selected from, e.g., astructure represented by Formula 2, hydrogen, deuterium, —F, —Cl, —Br,—I, a hydroxyl group, a cyano group, a nitro group, a substituted orunsubstituted C₁-C₆₀ alkyl group, a substituted or unsubstituted C₂-C₆₀alkenyl group, a substituted or unsubstituted C₂-C₆₀ alkynyl group, asubstituted or unsubstituted C₁-C₆₀ alkoxy group, a substituted orunsubstituted C₃-C₁₀ cycloalkyl group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀cycloalkenyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀ arylgroup, a substituted or unsubstituted C₆-C₆₀ aryloxy group, asubstituted or unsubstituted C₆-C₆₀ arylthio group, a substituted orunsubstituted C₁-C₆₀ heteroaryl group, a substituted or unsubstitutedmonovalent non-aromatic condensed polycyclic group, a substituted orunsubstituted monovalent non-aromatic condensed heteropolycyclic group,—Si(Q₁)(Q₂)(Q₃), —N(Q₁)(Q₂), —B(Q₁)(Q₂), —C(═O)(Q₁), —S(═O)₂(Q₁), and—P(═O)(Q₁)(Q₂). In an implementation, at least one selected from R₁ toR₁₀ may have a structure represented by Formula 2.

In one or more embodiments, R₁₁ and R₁₂ in Formula 1 may eachindependently be selected from a substituted or unsubstituted C₁-C₆₀alkyl group, a substituted or unsubstituted C₆-C₆₀ aryl group, and asubstituted or unsubstituted C₁-C₆₀ heteroaryl group.

In one or more embodiments, R₁₁ and R₁₂ in Formula 1 may eachindependently be selected from:

a methyl group, an ethyl group, a propyl group, an isobutyl group, asec-butyl group, a ter-butyl group, a pentyl group, an iso-amyl group,and a hexyl group; and

a methyl group, an ethyl group, a propyl group, an isobutyl group, asec-butyl group, a ter-butyl group, a pentyl group, an iso-amyl group,and a hexyl group, each substituted with at least one selected fromdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amino group, a C₁-C₆₀ alkyl group, a C₆-C₆₀ aryl group, and aC₂-C₆₀ heteroaryl group.

In one or more embodiments, R₁₁ and R₁₂ in Formula 1 may eachindependently be a methyl group or a phenyl group.

Ar₂ in Formula 1 may be selected from a substituted or unsubstitutedC₆-C₆₀ aryl group, a substituted or unsubstituted C₆-C₆₀ aryloxy group,a substituted or unsubstituted C₆-C₆₀ arylthio group, and a substitutedor unsubstituted C₁-C₆₀ heteroaryl group.

In one or more embodiments, Ar₂ and R₁₃ in Formula 1 may eachindependently be selected from:

a phenyl group, a biphenyl group, a terphenyl group, a pentalenyl group,an indenyl group, a naphthyl group, an azulenyl group, a heptalenylgroup, an indacenyl group, an acenaphthyl group, a phenalenyl group, aphenanthrenyl group, an anthracenyl group, a fluoranthenyl group, atriphenylenyl group, a pyrenyl group, a chrysenyl group, a naphthacenylgroup, a picenyl group, a perylenyl group, a pentaphenyl group, ahexacenyl group, a pentacenyl group, a rubicenyl group, a coronenylgroup, and an ovalenyl group; and

a phenyl group, a biphenyl group, a terphenyl group, a pentalenyl group,an indenyl group, a naphthyl group, an azulenyl group, a heptalenylgroup, an indacenyl group, an acenaphthyl group, a phenalenyl group, aphenanthrenyl group, an anthracenyl group, a fluoranthenyl group, atriphenylenyl group, a pyrenyl group, a chrysenyl group, a naphthacenylgroup, a picenyl group, a perylenyl group, a pentaphenyl group, ahexacenyl group, a pentacenyl group, a rubicenyl group, a coronenylgroup, and an ovalenyl group, each substituted with at least oneselected from hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, acyano group, a nitro group, an amino group, an amidino group, ahydrazine group, a hydrazone group, a carboxylic acid group or a saltthereof, a sulfonic acid group or a salt thereof, a phosphoric acidgroup or a salt thereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, aphenyl group, a biphenyl group, a terphenyl group, a pentalenyl group,an indenyl group, a naphthyl group, an azulenyl group, a heptalenylgroup, an indacenyl group, an acenaphthyl group, a phenalenyl group, aphenanthrenyl group, an anthracenyl group, a fluoranthenyl group, atriphenylenyl group, a pyrenyl group, a chrysenyl group, a naphthacenylgroup, a picenyl group, a perylenyl group, a pentaphenyl group, ahexacenyl group, a pentacenyl group, a rubicenyl group, a coronenylgroup, and an ovalenyl group.

In an implementation, Ar₂ and R₁₃ in Formula 1 may be separate or linkedto a neighboring substituent to form a substituted or unsubstitutedbenzene group, a substituted or unsubstituted naphthalene group, asubstituted or unsubstituted fluorene group, a substituted orunsubstituted spiro-fluorene group, a substituted or unsubstitutedindene group, a substituted or unsubstituted pyrrole group, asubstituted or unsubstituted thiophene group, a substituted orunsubstituted furan group, a substituted or unsubstituted imidazolegroup, a substituted or unsubstituted pyrazole group, a substituted orunsubstituted thiazole group, a substituted or unsubstituted isothiazolegroup, a substituted or unsubstituted oxazole group, a substituted orunsubstituted isoxazole group, a substituted or unsubstituted pyridinegroup, a substituted or unsubstituted pyrazine group, a substituted orunsubstituted pyrimidine group, a substituted or unsubstitutedpyridazine group, a substituted or unsubstituted quinoline group, asubstituted or unsubstituted isoquinoline group, a substituted orunsubstituted benzoquinoline group, a substituted or unsubstitutedquinoxaline group, a substituted or unsubstituted quinazoline group, asubstituted or unsubstituted carbazole group, a substituted orunsubstituted benzimidazole group, a substituted or unsubstitutedbenzofuran group, a substituted or unsubstituted benzothiophene group, asubstituted or unsubstituted isobenzothiophene group, a substituted orunsubstituted benzoxazole group, a substituted or unsubstitutedisobenzoxazole group, a substituted or unsubstituted triazole group, asubstituted or unsubstituted oxadiazole group, a substituted orunsubstituted triazine group, a substituted or unsubstituteddibenzofuran group, or a substituted or unsubstituted dibenzothiophenegroup.

At least one substituent selected from a substituent(s) of thesubstituted benzene group, the substituted naphthalene group, thesubstituted fluorene group, the substituted spiro-fluorene group, thesubstituted indene group, the substituted pyrrole group, the substitutedthiophene group, the substituted furan group, the substituted imidazolegroup, the substituted pyrazole group, the substituted thiazole group,the substituted isothiazole group, the substituted oxazole group, thesubstituted isoxazole group, the substituted pyridine group, thesubstituted pyrazine group, the substituted pyrimidine group, thesubstituted pyridazine group, the substituted quinoline group, thesubstituted isoquinoline group, the substituted benzoquinoline group,the substituted quinoxaline group, the substituted quinazoline group,the substituted carbazole group, the substituted benzimidazole group,the substituted benzofuran group, the substituted benzothiophene group,the substituted isobenzothiophene group, the substituted benzoxazolegroup, the substituted isobenzoxazole group, the substituted triazolegroup, the substituted oxadiazole group, the substituted triazine group,the substituted dibenzofuran group, and the substituted dibenzothiophenegroup may be selected from deuterium, —F, -CI, —Br, —I, a cyano group,and a C₁-C₆₀ alkyl group.

In one or more embodiments, Ar₂ and R₁₃ in Formula 1 may eachindependently be selected from:

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, aphenanthrenyl group, an anthracenyl group, a fluoranthenyl group, atriphenylenyl group, and a pyrenyl group; and

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, aphenanthrenyl group, an anthracenyl group, a fluoranthenyl group, atriphenylenyl group, and a pyrenyl group, each substituted withdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amino group, an amidino group, a hydrazine group, a hydrazonegroup, a carboxylic acid group or a salt thereof, a sulfonic acid groupor a salt thereof, a phosphoric acid group or a salt thereof, a C₁-C_(m)alkyl group, or a C₁-C₂₀ alkoxy group, or

Ar₂ and R₁₃ in Formula 1 may be separate or may be linked to aneighboring substituent to form a substituted or unsubstituted benzene,a substituted or unsubstituted naphthalene, a substituted orunsubstituted fluorene, a substituted or unsubstituted spiro-fluorene, asubstituted or unsubstituted pyridine, a substituted or unsubstitutedpyrazine, a substituted or unsubstituted pyrimidine, a substituted orunsubstituted pyridazine, a substituted or unsubstituted quinoline, asubstituted or unsubstituted isoquinoline, a substituted orunsubstituted quinoxaline, a substituted or unsubstituted quinazoline,or a substituted or unsubstituted triazine.

At least one substituent selected from a substituent(s) of thesubstituted benzene, the substituted naphthalene, the substitutedfluorene, the substituted spiro-fluorene, the substituted pyridine, thesubstituted pyrazine, the substituted pyrimidine, the substitutedpyridazine, the substituted quinoline, the substituted isoquinoline, thesubstituted quinoxaline, the substituted quinazoline, and thesubstituted triazine may be selected from deuterium, —F, —Cl, —Br, —I, acyano group, and a C₁-C₆₀ alkyl group.

In one or more embodiments, Ar_(e) in Formula 1 may be selected from:

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, aspiro-fluorene-benzofluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, atriphenylenyl group, a pyrenyl group, and a chrysenyl group;

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a Spiro-bifluorenyl group, aspiro-fluorene-benzofluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, atriphenylenyl group, a pyrenyl group, and a chrysenyl group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C ₁₀ alkyl group, a C₁-C₁₀alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, anaphthyl group, a fluorenyl group, a spiro-bifluorenyl group, aSpiro-fluorene-benzofluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, atriphenylenyl group, a pyrenyl group, and a chrysenyl group.

In one or more embodiments, Ar₂ in Formula 1 may be one selected fromgroups represented by Formulae 5-1 to 5-52:

In Formulae 5-1 to 5-52,

Z₃₁ to Z₃₅ may each independently be selected from hydrogen, deuterium,—F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, anamidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀ alkylgroup, a C₁-C₂₀ alkenyl group, a C₁- C₂₀ alkynyl group, a C₁-C₂₀ alkoxygroup, a phenyl group, a biphenyl group, a terphenyl group, a naphthylgroup, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenylgroup, a dibenzofluorenyl group, a phenanthrenyl group, an anthracenylgroup, a pyrenyl group, a chrysenyl group, a pyridinyl group, apyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a quinolinylgroup, an isoquinolinyl group, a quinoxalinyl group, a quinazolinylgroup, a carbazolyl group, a triazinyl group, —Si(Q₃₁)(Q₃₂)(Q₃₃),—N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁), —S(═O)₂(Q₃₁), and—P(═O)(Q₃₁)(Q₃₂),

Q₁ to Q₃ and Q₃₁ to Q₃₃ may each independently be selected from a C₁-C₁₀alkyl group, a C₁-C₁₀ alkoxy group, a phenyl group, a phenyl groupsubstituted with a C1-C10 alkyl group, a biphenyl group, a terphenylgroup, a naphthyl group, and a dibenzofuranyl group.

e2 may be 1 or 2,

e3 may be an integer from1 to 3,

e4 may be an integer from 1 to 4,

e5 may be an integer from 1 to 5,

e6 may be an integer from 1 to 6,

e7 may be an integer from 1 to 7,

e9 may be an integer from 1 to 9, and

* indicates a binding site to a neighboring atom.

In one or more embodiments, Ar_(e) in Formula 1 may be represented byone of Formulae 6-1 to 6-4:

wherein * indicates a binding site to a neighboring atom.

L₁ in Formula 2 may be selected from a substituted or unsubstitutedC₃-C₁₀ cycloalkylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkylene group, a substituted or unsubstituted C₃-C₁₀cycloalkenylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenylene group, a substituted or unsubstituted C₆-C₆₀arylene group, a substituted or unsubstituted C₁-C₆₀ heteroarylenegroup, a substituted or unsubstituted divalent non-aromatic condensedpolycyclic group, and a substituted or unsubstituted divalentnon-aromatic condensed heteropolycyclic group.

In one or more embodiments, L₁ in Formula 2 may be selected from:

a phenylene group, a pentalenylene group, an indenylene group, anaphthylene group, an azulenylene group, a heptalenylene group, anindacenylene group, an acenaphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a spiro-fluorene-benzofluorenylene group, abenzofluorenylene group, a dibenzofluorenylene group, a phenalenylenegroup, a phenanthrenylene group, an anthracenylene group, afluoranthenylene group, a triphenylenylene group, a pyrenylene group, achrysenylene group, a naphthacenylene group, a picenylene group, aperylenylene group, a pentaphenylene group, a hexacenylene group, apentacenylene group, a rubicenylene group, a coronenylene group, anovalenylene group, a pyrrolylene group, a thiophenylene group, afuranylene group, an imidazolylene group, a pyrazolylene group, athiazolylene group, an isothiazolylene group, an oxazolylene group, anisoxazolylene group, a pyridinylene group, a pyrazinylene group, apyrimidinylene group, a pyridazinylene group, an isoindolylene group, anindolylene group, an indazolylene group, a purinylene group, aquinolinylene group, an isoquinolinylene group, a benzoquinolinylenegroup, a phthalazinylene group, a naphthyridinylene group, aquinoxalinylene group, a quinazolinylene group, a cinnolinylene group, acarbazolylene group, a phenanthridinylene group, an acridinylene group,a phenanthrolinylene group, a phenazinylene group, a benzimidazolylenegroup, a benzofuranylene group, a benzothiophenylene group, anisobenzothiazolylene group, a benzoxazolylene group, anisobenzoxazolylene group, a triazolylene group, a tetrazolylene group,an oxadiazolylene group, a triazinylene group, a dibenzofuranylenegroup, a dibenzothiophenylene group, a dibenzosilolylene group, abenzocarbazolylene group, a dibenzocarbazolylene group, athiadiazolylene group, an imidazopyridinylene group, and animidazopyrimidinylene group; and

a phenylene group, a pentalenylene group, an indenylene group, anaphthylene group, an azulenylene group, a heptalenylene group, anindacenylene group, an acenaphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a spiro-fluorene-benzofluorenylene group, abenzofluorenylene group, a dibenzofluorenylene group, a phenalenylenegroup, a phenanthrenylene group, an anthracenylene group, afluoranthenylene group, a triphenylenylene group, a pyrenylene group, achrysenylene group, a naphthacenylene group, a phenylene group, aperylenylene group, a pentaphenylene group, a hexacenylene group, apentacenylene group, a rubicenylene group, a coronenylene group, anovalenylene group, a pyrrolylene group, a thiophenylene group, afuranylene group, an imidazolylene group, a pyrazolylene group, athiazolylene group, an isothiazolylene group, an oxazolylene group, anisoxazolylene group, a pyridinylene group, a pyrazinylene group, apyrimidinylene group, a pyridazinylene group, an isoindolylene group, anindolylene group, an indazolylene group, a purinylene group, aquinolinylene group, an isoquinolinylene group, a benzoquinolinylenegroup, a phthalazinylene group, a naphthyridinylene group, aquinoxalinylene group, a quinazolinylene group, a cinnolinylene group, acarbazolylene group, a phenanthridinylene group, an acridinylene group,a phenanthrolinylene group, a phenazinylene group, a benzimidazolylenegroup, a benzofuranylene group, a benzothiophenylene group, anisobenzothiazolylene group, a benzoxazolylene group, anisobenzoxazolylene group, a triazolylene group, a tetrazolylene group,an oxadiazolylene group, a triazinylene group, a dibenzofuranylenegroup, a dibenzothiophenylene group, a dibenzosilolylene group, abenzocarbazolylene group, a dibenzocarbazolylene group, athiadiazolylene group, an imidazopyridinylene group, and animidazopyrimidinylene group, each substituted with at least one selectedfrom deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, anitro group, an amidino group, a hydrazino group, a hydrazono group, aC₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a cyclopentyl group, acyclohexyl group, a cycloheptyl group, a cyclopentenyl group, acyclohexenyl group, a phenyl group, a biphenyl group, a terphenyl group,a pentalenyl group, an indenyl group, a naphthyl group, an azulenylgroup, a heptalenyl group, an indacenyl group, an acenaphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, ananthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group,a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a rubicenyl group, a coronenyl group, an ovalenyl group, apyrrolyl group, a thiophenyl group, a furanyl group, an imidazolylgroup, a pyrazolyl group, a thiazolyl group, an isothiazolyl group, anoxazolyl group, an isoxazolyl group, a pyridinyl group, a pyrazinylgroup, a pyrimidinyl group, a pyridazinyl group, an isoindolyl group, anindolyl group, an indazolyl group, a purinyl group, a quinolinyl group,an isoquinolinyl group, a benzoquinolinyl group, a phthalazinyl group, anaphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, acinnolinyl group, a carbazolyl group, a phenanthridinyl group, anacridinyl group, a phenanthrolinyl group, a phenazinyl group, abenzimidazolyl group, a benzofuranyl group, a benzothiophenyl group, anisobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolyl group,a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinylgroup, a dibenzofuranyl group, a dibenzothiophenyl group, adibenzosilolylene group, a benzocarbazolyl group, a dibenzocarbazolylgroup, a thiadiazolyl group, an imidazopyridinyl group, animidazopyrimidinyl group, —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂),—B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁), —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂),

Q₃₁ to Q₃₃ may each independently be selected from a C₁-C₁₀ alkyl group,a C₁-C₁₀ alkoxy group, a phenyl group, a phenyl group substituted with aC₁-C ₁₀ alkyl group, a biphenyl group, a terphenyl group, a naphthylgroup, and a dibenzofuranyl group.

In one or more embodiments, L₁ in Formula 2 may be represented by one ofFormulae 3-1 to 3-49 (e.g., Formula 3-1 to 3-43, 3-43′, and 3-44 to3-49).

In Formulae 3-1 to 3-49,

Y₁ may be O, S, C(Z₃)(Z₄), N(Z₅), or Si(Z₆)(Z₇),

Z₁ to Z₇ may each independently be selected from hydrogen, deuterium,—F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, anamino group, an amidino group, a hydrazine group, a hydrazone group, acarboxylic acid group or a salt thereof, a sulfonic acid group or a saltthereof, a phosphoric acid group or a salt thereof, a C₁-C₂₀ alkylgroup, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, a naphthyl group, a fluorenyl group, aspiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenylgroup, a phenanthrenyl group, an anthracenyl group, a pyrenyl group, achrysenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinylgroup, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group,a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, adibenzofuranyl group, a dibenzothiophenyl group, a triazinyl group, abenzimidazolyl group, a phenanthrolinyl group, and —Si(Q₃₃)(Q₃₄)(Q₃₅),

wherein Q₃₃ to Q₃₅ may each independently be selected from a C₁-C₁₀alkyl group, a C₁-C₁₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, and a naphthyl group,

d2 may be an integer from 0 to 2,

d3 may be an integer from 0 to 3,

d4 may be an integer from 0 to 4,

d5 may be an integer from 0 to 5,

d6 may be an integer from 0 to 6,

d8 may be an integer from 0 to 8, and

* and *' each indicate a binding site to a neighboring atom.

In one or more embodiments, L₁ in Formula 1 may be selected from groupsrepresented by Formulae 4-1 to 4-6:

wherein * and *' in Formulae 4-1 and 4-6 each indicate a binding site toa neighboring atom.

a1 in Formula 1 indicates the number of L₁(s). al may be 0, 1, 2, or 3.When a1 is two or three, the two or three L₁(s) may be identical to ordifferent from each other. When al is zero, *-(L₁)_(a1)-*′ may be asingle bond.

In one or more embodiments, al in Formula 1 may be 0, 1, or 2.

In one or more embodiments, al in Formula 1 may be 0 or 1.

In one or more embodiments, al in Formula 1 may be 1 or 2.

Ar₁ in Formula 2 may be a substituted or unsubstituted C₁-C₆₀heterocyclic group having at least one *—N═*′ moiety.

For example, An in Formula 1 may be selected from:

an imidazolyl group, a pyrazole group, a thiazolyl group, anisothiazolyl group, an oxazolyl group, an isoxazolyl group, a pyridinylgroup, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, anindazolyl group, a purinyl group, a quinolinyl group, an isoquinolinylgroup, a benzoquinolinyl group, a phthalazinyl group, a naphthyridinylgroup, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, aphenazinyl group, a benzimidazolyl group, an isobenzothiazolyl group, abenzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, atetrazolyl group, an oxadiazolyl group, a triazinyl group, athiadiazolyl group, an imidazopyridinyl group, an imidazopyrimidinylgroup, and an azacarbazolyl group; and

an imidazolyl group, a pyrazole group, a thiazolyl group, anisothiazolyl group, an oxazolyl group, an isoxazolyl group, a pyridinylgroup, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, anindazolyl group, a purinyl group, a quinolinyl group, an isoquinolinylgroup, a benzoquinolinyl group, a phthalazinyl group, a naphthyridinylgroup, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, aphenazinyl group, a benzimidazolyl group, an isobenzothiazolyl group, abenzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, atetrazolyl group, an oxadiazolyl group, a triazinyl group, athiadiazolyl group, an imidazopyridinyl group, an imidazopyrimidinylgroup, and an azacarbazolyl group, each substituted with deuterium, —F,—Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidinogroup, a hydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, or aC₁-C₂₀ alkoxy group.

In one or more embodiments, Ar₁ in Formula 1 may be selected from groupsrepresented by Formulae 7-1 to 7-59:

wherein, in Formulae 7-1 to 7-59,

Z₅₁ and Z₅₂ may each independently be selected from hydrogen, deuterium,—F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, anamidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀ alkylgroup, a C₁-C₂₀ alkoxy group, an imidazolyl group, a pyrazole group, athiazolyl group, an isothiazolyl group, an oxazolyl group, an isoxazolylgroup, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, apyridazinyl group, an indazolyl group, a purinyl group, a quinolinylgroup, an isoquinolinyl group, a benzoquinolinyl group, a phthalazinylgroup, a naphthyridinyl group, a quinoxalinyl group, a quinazolinylgroup, a cinnolinyl group, a phenanthridinyl group, an acridinyl group,a phenanthrolinyl group, a phenazinyl group, a benzimidazolyl group, anisobenzothiazolyl group, a benzoxazolyl group, an isobenzoxazolyl group,a triazolyl group, a tetrazolyl group, an oxadiazolyl group, a triazinylgroup, a thiadiazolyl group, an imidazopyridinyl group, animidazopyrimidinyl group, and an azacarbazolyl group,

g2 may be an integer from 0 to 2,

g3 may be an integer from 0 to 3,

g4 may be an integer from 0 to 4,

g5 may be an integer from 0 to 5,

g6 may be an integer from 0 to 6, and

* and *′ each indicate a binding site to a neighboring atom.

For example, the polycyclic compound may be represented by one ofFormulae 1-1 to 1-4:

wherein, in Formulae 1-1 to 1-4,

L₁, al, R₁ to R₁₀, and Ar₂ are the same as described above.

In one or more embodiments, when X₁ in Formula 1 is N(R₁₃), the compoundrepresented by Formula 1 may be represented by Formula 11 or 12.

R₁ to R₁₀ in Formulae 11 and 12 are the same as described above.

Ring A₁ in Formula 11 may be selected from a substituted orunsubstituted benzene, a substituted or unsubstituted naphthalene, asubstituted or unsubstituted fluorene, a substituted or unsubstitutedspiro-fluorene, a substituted or unsubstituted indene, a substituted orunsubstituted pyrrole, a substituted or unsubstituted thiophene, asubstituted or unsubstituted furan, a substituted or unsubstitutedimidazole, a substituted or unsubstituted pyrazole, a substituted orunsubstituted thiazole, a substituted or unsubstituted isothiazole, asubstituted or unsubstituted oxazole, a substituted or unsubstitutedisoxazole, a substituted or unsubstituted pyridine, a substituted orunsubstituted pyrazine, a substituted or unsubstituted pyrimidine, asubstituted or unsubstituted pyridazine, a substituted or unsubstitutedquinoline, a substituted or unsubstituted isoquinoline, a substituted orunsubstituted benzoquinoline, a substituted or unsubstitutedquinoxaline, a substituted or unsubstituted quinazoline, a substitutedor unsubstituted carbazole, a substituted or unsubstitutedbenzimidazole, a substituted or unsubstituted benzofuran, a substitutedor unsubstituted benzothiophene, a substituted or unsubstitutedisobenzothiophene, a substituted or unsubstituted benzoxazole, asubstituted or unsubstituted isobenzoxazole, a substituted orunsubstituted triazole, a substituted or unsubstituted oxadiazole, asubstituted or unsubstituted triazine, a substituted or unsubstituteddibenzofuran, and a substituted or unsubstituted dibenzothiophene.

In one or more embodiments, ring A₁ in Formula 11 may be selected from asubstituted or unsubstituted benzene, a substituted or unsubstitutednaphthalene, a substituted or unsubstituted fluorene, and a substitutedor unsubstituted spiro-fluorene.

R₂₁ and R₂₂ in Formula 12 may each independently be selected fromhydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, a substituted or unsubstituted C₁-C₆₀ alkyl group, asubstituted or unsubstituted C₂-C₆₀ alkenyl group, a substituted orunsubstituted C₂ ⁻C₆₀ alkynyl group, a substituted or unsubstitutedC₁-C₆₀ alkoxy group, a substituted or unsubstituted C₃-C₁₀ cycloalkylgroup, a substituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, asubstituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted orunsubstituted C₁-C₁₀ heterocycloalkenyl group, a substituted orunsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₆-C₆₀aryloxy group, a substituted or unsubstituted C₆-C₆₀ arylthio group, asubstituted or unsubstituted C₁-C₆₀ heteroaryl group, a substituted orunsubstituted monovalent non-aromatic condensed polycyclic group, and asubstituted or unsubstituted monovalent non-aromatic condensedheteropolycyclic group.

In one or more embodiments, R₂₁ and R₂₂ may each independently beselected from:

hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, a phenyl group, a biphenyl group, a terphenyl group, apentalenyl group, an indenyl group, a naphthyl group, an azulenyl group,a heptalenyl group, an indacenyl group, an acenaphthyl group, aphenalenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a naphthacenyl group, a picenyl group, a perylenyl group, apentaphenyl group, a hexacenyl group, a pentacenyl group, a rubicenylgroup, a coronenyl group, and an ovalenyl group; and

a phenyl group, a biphenyl group, a terphenyl group, a pentalenyl group,an indenyl group, a naphthyl group, an azulenyl group, a heptalenylgroup, an indacenyl group, an acenaphthyl group, a phenalenyl group, aphenanthrenyl group, an anthracenyl group, a fluoranthenyl group, atriphenylenyl group, a pyrenyl group, a chrysenyl group, a naphthacenylgroup, a picenyl group, a perylenyl group, a pentaphenyl group, ahexacenyl group, a pentacenyl group, a rubicenyl group, a coronenylgroup, and an ovalenyl group, each substituted with at least oneselected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amino group, an amidino group, a hydrazinegroup, a hydrazone group, a carboxylic acid group or a salt thereof, asulfonic acid group or a salt thereof, a phosphoric acid group or a saltthereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, abiphenyl group, a terphenyl group, a pentalenyl group, an indenyl group,a naphthyl group, an azulenyl group, a heptalenyl group, an indacenylgroup, an acenaphthyl group, a phenalenyl group, a phenanthrenyl group,an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group,a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a rubicenyl group, a coronenyl group, and an ovalenyl group.

In one or more embodiments, the compound represented by Formula 11 maybe represented by Formula 11-1.

In Formula 11-1,

R₁ to R₁₀ are the same as descried above.

R₂₃ in Formula 11-1 may be selected from hydrogen, deuterium, —F, —Cl,—Br, —I, a hydroxyl group, a cyano group, a nitro group, a substitutedor unsubstituted C₁-C₆₀ alkyl group, a substituted or unsubstitutedC₂-C₆₀ alkenyl group, a substituted or unsubstituted C₂-C₆₀ alkynylgroup, a substituted or unsubstituted C₁-C₆₀ alkoxy group, a substitutedor unsubstituted C₃-C₁₀ cycloalkyl group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀cycloalkenyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀ arylgroup, a substituted or unsubstituted C₆-C₆₀ aryloxy group, asubstituted or unsubstituted C₆-C₆₀ arylthio group, a substituted orunsubstituted C₁-C₆₀ heteroaryl group, a substituted or unsubstitutedmonovalent non-aromatic condensed polycyclic group, and a substituted orunsubstituted monovalent non-aromatic condensed heteropolycyclic group,or may be linked to two or more neighboring R₂₃(s) to form a substitutedor unsubstituted ring.

r1 in Formula 11-1 may be an integer from 0 to 4,

wherein, when r1 is two or more, two or more R₂₃(s) may be identical toor different from each other.

In one or more embodiments, the polycyclic compound represented byFormula 1 may be represented by one of Formulae 21 to 24.

In Formulae 21 to 24,

X₁, L₁, Ar₁, Ar₂, R₁ to R₁₀, a1, and b1 are the same as described above.

In one or more embodiments, the polycyclic compound may be one selectedfrom Compounds A-1 to A-51.

The polycyclic compound represented by Formula 1 may have a structure inwhich some ring-forming atoms in a phenalene ring condensed with abenzothiophene or a benzofuran are modified with nitrogen atoms. Thus,it is possible to help prevent a reduction in efficiency under a lowcurrent condition by increasing electron mobility through molecularenergy adjustment. Also, charge balance in a device may be appropriatelyadjusted under a high current condition, thereby obtaining the effectsof increasing the lifespan and efficiency of the device.

Therefore, an electronic device (e.g., an organic light-emitting device)including the polycyclic compound represented by Formula 1 mayadvantageously have a low driving voltage, a high current density, andhigh efficiency.

A synthesis method for the polycyclic compound represented by Formula 1may be understood by referring to the following examples.

At least one polycyclic compound of Formula 1 may be used or includedbetween a pair of electrodes of an organic light-emitting device. Forexample, the polycyclic compound may be included in at least one layerselected from a hole transport region and an emission layer . In one ormore embodiments, the polycyclic compound represented by Formula 1 maybe used as a material for forming a capping layer positioned outside thepair of electrodes of the organic light-emitting device.

Accordingly, provided is an organic light-emitting device including: afirst electrode; a second electrode facing the first electrode; and anorganic layer between the first electrode and the second electrode, theorganic layer including an emission layer, wherein the organic layerincludes at least one polycyclic compound represented by Formula 1.

The expression “(an organic layer) includes at least one of thepolycyclic compounds” used herein may include a case in which “(anorganic layer) includes identical polycyclic compounds represented byFormula 1” and a case in which “(an organic layer) includes two or moredifferent polycyclic compounds represented by Formula 1.”

For example, the organic layer may include, as the polycyclic compound,only Compound 1. In this regard, Compound 1 may exist in an emissionlayer of the organic light-emitting device. In one or more embodiments,the organic layer may include, as the polycyclic compound, Compound 1and Compound 2. In this regard, Compound 1 and Compound 2 may exist inan identical layer (for example, Compound 1 and Compound 2 may all existin an emission layer), or different layers (for example, Compound 1 mayexist in an emission layer and Compound 2 may exist in an electrontransport layer).

According to one or more embodiments,

the first electrode of the organic light-emitting device may be ananode,

the second electrode of the organic light-emitting device may be acathode,

the organic layer of the organic light-emitting device may furtherinclude a hole transport region between the first electrode and theemission layer and an electron transport region between the emissionlayer and the second electrode,

the hole transport region may include at least one layer selected from ahole injection layer, a hole transport layer, a buffer layer, anemission auxiliary layer, and an electron blocking layer, and

the electron transport region may include at least one layer selectedfrom a hole blocking layer, an electron transport layer, and an electroninjection layer. The electron transport region may include thepolycyclic compound represented by Formula 1.

In one or more embodiments, the electron transport region of the organiclight-emitting device may include an electron transport layer and anelectron injection layer, and at least one of the electron transportlayer and the electron injection layer may include the polycycliccompound represented by Formula 1.

In the organic light-emitting device, at least one layer selected fromthe electron transport layer and the electron injection layer mayfurther include alkali metal, alkaline earth metal, rare-earth metal, analkali metal compound, an alkaline earth-metal compound, a rare-earthmetal compound, an alkali metal complex, an alkaline earth-metalcomplex, a rare-earth metal complex, or any combinations thereof.

The emission layer of the organic light-emitting device includes adopant and a host, and the host may include at least one selected froman anthracene-based compound, a pyrene-based compound, and aspiro-bifluorene-based compound.

The term “organic layer” as used herein refers to a single layer and/ora plurality of layers between the first electrode and the secondelectrode of an organic light-emitting device. A material included inthe “organic layer” is not limited to an organic material.

FIG. 1 illustrates a schematic view of an organic light-emitting device10 according to an embodiment. The organic light-emitting device 10includes a first electrode 110, an organic layer 150, and a secondelectrode 190.

Hereinafter, the structure of the organic light-emitting device 10according to an embodiment and a method of manufacturing the organiclight-emitting device 10 will be described in connection with FIG. 1.

In an implementation, a substrate may be additionally disposed under thefirst electrode 110 or above the second electrode 190. The substrate maybe a glass substrate or a plastic substrate, each having excellentmechanical strength, thermal stability, transparency, surfacesmoothness, ease of handling, and water-resistance.

The first electrode 110 may be formed by depositing or sputtering amaterial for forming the first electrode 110 on the substrate. When thefirst electrode 110 is an anode, the material for forming the firstelectrode 110 may be selected from materials with a high work functionto facilitate hole injection.

The first electrode 110 may be a reflective electrode, asemi-transmissive electrode, or a transmissive electrode. When the firstelectrode 110 is a transmissible electrode, a material for forming thefirst electrode 110 may be selected from indium tin oxide (ITO), indiumzinc oxide (IZO), tin oxide (SnO₂), zinc oxide (ZnO), and anycombinations thereof When the first electrode 110 is a semi-transmissiveelectrode or a reflective electrode, as a material for forming the firstelectrode 110, magnesium (Mg), silver (Ag), aluminum (Al),aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In),magnesium-silver (Mg—Ag), or any combination thereof may be used.

The first electrode 110 may have a single-layered structure, or amulti-layered structure including two or more layers. For example, thefirst electrode 110 may have a three-layered structure of ITO/Ag/ITO.

The organic layer 150 is disposed on the first electrode 110. Theorganic layer 150 may include an emission layer.

The organic layer 150 may further include a hole transport regionbetween the first electrode 110 and the emission layer, and an electrontransport region between the emission layer and the second electrode190.

The hole transport region may have i) a single-layered structureincluding a single layer including a single material, ii) asingle-layered structure including a single layer including a pluralityof different materials, or iii) a multi-layered structure having aplurality of layers including a plurality of different materials.

The hole transport region may include at least one layer selected from ahole injection layer, a hole transport layer, an emission auxiliarylayer, and an electron blocking layer.

For example, the hole transport region may have a single-layeredstructure including a single layer including a plurality of differentmaterials, or a multi-layered structure having a hole injectionlayer/hole transport layer structure, a hole injection layer/holetransport layer/emission auxiliary layer structure, a hole injectionlayer/emission auxiliary layer structure, a hole transportlayer/emission auxiliary layer structure, or a hole injection layer/holetransport layer/electron blocking layer structure, wherein, for eachstructure, constituting layers are sequentially stacked from the firstelectrode 110 in this stated order.

The hole transport region may include at least one selected fromm-MTDATA, TDATA, 2-TNATA, NPB(NPD), β-NPB, TPD, Spiro-TPD, Spiro-NPB,methylated-NPB, TAPC, HMTPD, 4,4′,4″-tris(N-carbazolyl)triphenylamine(TCTA), polyaniline/dodecylbenzenesulfonic acid (Pani/DBSA), PEDOT/PSS(poly(3,4-ethylenedioxythiophene)/poly(4-styrenesulfonate)),polyaniline/camphor sulfonic acid (Pani/CSA),polyaniline/poly(4-styrenesulfonate) (Pani/PSS), a compound representedby Formula 201, and a compound represented by Formula 202:

In Formulae 201 and 202,

L₂₀₁ to L₂₀₄ are each independently selected from a substituted orunsubstituted C₃-C₁₀ cycloalkylene group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkylene group, a substituted or unsubstituted C₃-C₁₀cycloalkenylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenylene group, a substituted or unsubstituted C₆-C₆₀arylene group, a substituted or unsubstituted C₁-C₆₀ heteroarylenegroup, a substituted or unsubstituted divalent non-aromatic condensedpolycyclic group, and a substituted or unsubstituted divalentnon-aromatic condensed heteropolycyclic group,

L₂₀₅ may be selected from *—O—*′, *—S—*′, *—N(Q₂₀₁)-*′, a substituted orunsubstituted C₁-C₂₀ alkylene group, a substituted or unsubstitutedC₂-C₂₀ alkenylene group, a substituted or unsubstituted C₃-C₁₀cycloalkylene group, a substituted or unsubstituted heterocycloalkylenegroup, a substituted or unsubstituted C₃-C₁₀ cycloalkenylene group, asubstituted or unsubstituted C₁-C₁₀ heterocycloalkenylene group, asubstituted or unsubstituted C₆-C₆₀ arylene group, a substituted orunsubstituted C₁-C₆₀ heteroarylene group, a substituted or unsubstituteddivalent non-aromatic condensed polycyclic group, and a substituted orunsubstituted divalent non-aromatic condensed heteropolycyclic group,

xa1 to xa4 may each independently be an integer from 0 to 3,

xa5 may be an integer from 1 to 10, and

R₂₀₁ to R₂₀₄ and Q₂₀₁ may each independently be selected from asubstituted or unsubstituted C₃-C₁₀ cycloalkyl group, a substituted orunsubstituted heterocycloalkyl group, a substituted or unsubstitutedC₃-C₁₀ cycloalkenyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenyl group, a substituted or unsubstituted C₆ ⁻C₆₀ arylgroup, a substituted or unsubstituted C₆-C₆₀ aryloxy group, asubstituted or unsubstituted C₆-C₆₀ arylthio group, a substituted orunsubstituted C₁-C₆₀ heteroaryl group, a substituted or unsubstitutedmonovalent non-aromatic condensed polycyclic group, and a substituted orunsubstituted monovalent non-aromatic condensed heteropolycyclic group.

For example, in Formula 202, R₂₀₁ and R₂₀₂ may optionally be linked viaa single bond, a dimethyl-methylene group, or a diphenyl-methylenegroup, and R₂₀₃ and R₂₀₄ may optionally be linked via a single bond, adimethyl-methylene group, or a diphenyl-methylene group.

In one or more embodiments, in Formulae 201 and 202,

L₂₀₁ to L₂₀₅ may each independently be selected from:

a phenylene group, a pentalenylene group, an indenylene group, anaphthylene group, an azulenylene group, a heptalenylene group, anindacenylene group, an acenaphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenalenylene group, a phenanthrenylenegroup, an anthracenylene group, a fluoranthenylene group, atriphenylenylene group, a pyrenylene group, a chrysenylene group, anaphthacenylene group, a picenylene group, a perylenylene group, apentaphenylene group, a hexacenylene group, a pentacenylene group, arubicenylene group, a coronenylene group, an ovalenylene group, athiophenylene group, a furanylene group, a carbazolylene group, anindolylene group, an isoindolylene group, a benzofuranylene group, abenzothiophenylene group, a dibenzofuranylene group, adibenzothiophenylene group, a benzocarbazolylene group, adibenzocarbazolylene group, a dibenzosilolylene group, and apyridinylene group; and

a phenylene group, a pentalenylene group, an indenylene group, anaphthylene group, an azulenylene group, a heptalenylene group, anindacenylene group, an acenaphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenalenylene group, a phenanthrenylenegroup, an anthracenylene group, a fluoranthenylene group, atriphenylenylene group, a pyrenylene group, a chrysenylene group, anaphthacenylene group, a picenylene group, a perylenylene group, apentaphenylene group, a hexacenylene group, a pentacenylene group, arubicenylene group, a coronenylene group, an ovalenylene group, athiophenylene group, a furanylene group, a carbazolylene group, anindolylene group, an isoindolylene group, a benzofuranylene group, abenzothiophenylene group, a dibenzofuranylene group, adibenzothiophenylene group, a benzocarbazolylene group, adibenzocarbazolylene group, a dibenzosilolylene group, and apyridinylene group, each substituted with at least one selected fromdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a cyclopentyl group, a cyclohexylgroup, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group,a phenyl group, a biphenyl group, a terphenyl group, a phenyl groupsubstituted with a C1-C10 alkyl group, a phenyl group substituted with—F, a pentalenyl group, an indenyl group, a naphthyl group, an azulenylgroup, a heptalenyl group, an indacenyl group, an acenaphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, ananthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group,a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a rubicenyl group, a coronenyl group, an ovalenyl group, athiophenyl group, a furanyl group, a carbazolyl group, an indolyl group,an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, a dibenzosilolyl group, a pyridinylgroup, —Si(Q₃₁)(Q₃₂)(Q₃₃), and —N(Q₃₁)(Q₃₂),

wherein Q₃₁ to Q₃₃ may each independently be selected from a C₁-C₁₀alkyl group, a C₁-C₁₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, and a naphthyl group.

In one or more embodiments, xal to xa4 may each independently be 0, 1,or 2.

In one or more embodiments, xa5 may be 1, 2, 3, or 4.

In one or more embodiments, R₂₀₁ to R₂₀₄ and Q₂₀₁ may each independentlybe selected from a phenyl group, a biphenyl group, a terphenyl group, apentalenyl group, an indenyl group, a naphthyl group, an azulenyl group,a heptalenyl group, an indacenyl group, an acenaphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, ananthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group,a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a rubicenyl group, a coronenyl group, an ovalenyl group, athiophenyl group, a furanyl group, a carbazolyl group, an indolyl group,an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, a dibenzosilolyl group, and apyridinyl group; and

a phenyl group, a biphenyl group, a terphenyl group, a pentalenyl group,an indenyl group, a naphthyl group, an azulenyl group, a heptalenylgroup, an indacenyl group, an acenaphthyl group, a fluorenyl group, aspiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenylgroup, a phenalenyl group, a phenanthrenyl group, an anthracenyl group,a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, achrysenyl group, a naphthacenyl group, a picenyl group, a perylenylgroup, a pentaphenyl group, a hexacenyl group, a pentacenyl group, arubicenyl group, a coronenyl group, an ovalenyl group, a thiophenylgroup, a furanyl group, a carbazolyl group, an indolyl group, anisoindolyl group, a benzofuranyl group, a benzothiophenyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, a dibenzosilolyl group, and apyridinyl group, each substituted with at least one selected fromdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a cyclopentyl group, a cyclohexylgroup, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group,a phenyl group, a biphenyl group, a terphenyl group, a phenyl groupsubstituted with a C₁-C₁₀ alkyl group, a phenyl group substituted with—F, a pentalenyl group, an indenyl group, a naphthyl group, an azulenylgroup, a heptalenyl group, an indacenyl group, an acenaphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, ananthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group,a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a rubicenyl group, a coronenyl group, an ovalenyl group, athiophenyl group, a furanyl group, a carbazolyl group, an indolyl group,an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, a dibenzosilolyl group, a pyridinylgroup, —Si(Q₃₁)(Q₃₂)(Q₃₃), and —N(Q₃₁)(Q₃₂),

wherein Q₃₁ to Q₃₃ are the same as described above.

In one or more embodiments, at least one of R₂₀₁ to R₂₀₃ in Formula 201may each independently be selected from:

a fluorenyl group, a spiro-bifluorenyl group, a carbazolyl group, adibenzofuranyl group, and a dibenzothiophenyl group; and

a fluorenyl group, a spiro-bifluorenyl group, a carbazolyl group, adibenzofuranyl group, and a dibenzothiophenyl group, each substitutedwith at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxylgroup, a cyano group, a nitro group, an amidino group, a hydrazinogroup, a hydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, acyclopentyl group, a cyclohexyl group, a cycloheptyl group, acyclopentenyl group, a cyclohexenyl group, a phenyl group, a biphenylgroup, a terphenyl group, a phenyl group substituted with a C₁-C₁₀ alkylgroup, a phenyl group substituted with —F, a naphthyl group, a fluorenylgroup, a spiro-bifluorenyl group, a carbazolyl group, a dibenzofuranylgroup, and a dibenzothiophenyl group.

In one or more embodiments, in Formula 202, i) R₂₀₁ and R₂₀₂ may belinked via a single bond and/or ii) R₂₀₃ and R₂₀₄ may be linked via asingle bond.

In one or more embodiments, at least one of R₂₀₁ to R₂₀₄ in Formula 202may be selected from:

a carbazolyl group; and

a carbazolyl group, substituted with at least one selected fromdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a cyclopentyl group, a cyclohexylgroup, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group,a phenyl group, a biphenyl group, a terphenyl group, a phenyl groupsubstituted with a C₁-C₁₀ alkyl group, a phenyl group substituted with—F, a naphthyl group, a fluorenyl group, a spiro-bifluorenyl group, acarbazolyl group, a dibenzofuranyl group, and a dibenzothiophenyl group.

The compound represented by Formula 201 may be represented by Formula201A:

In one or more embodiments, the compound represented by Formula 201 maybe represented by Formula 201A(1) below:

In one or more embodiments, the compound represented by Formula 201 maybe represented by Formula 201A-1 below:

In one or more embodiments, the compound represented by Formula 202 maybe represented by Formula 202A:

In one or more embodiments, the compound represented by Formula 202 maybe represented by Formula 202A-1:

In Formulae 201A, 201A(1), 201A-1, 202A, and 202A-1,

L₂₀₁ to L₂₀₃, xa1 to xa3, xa5, and R₂₀₂ to R₂₀₄ may be the same asdescribed above,

R₂₁₁ and R₂₁₂ may be understood by referring to the description providedherein in connection with R₂₀₃.

R₂₁₃ to R₂₁₇ may each independently be selected from hydrogen,deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a cyclopentyl group, a cyclohexylgroup, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group,a phenyl group, a biphenyl group, a terphenyl group, a phenyl groupsubstituted with a C₁-C₁₀ alkyl group, a phenyl group substituted with—F, a pentalenyl group, an indenyl group, a naphthyl group, an azulenylgroup, a heptalenyl group, an indacenyl group, an acenaphthyl group, afluorenyl group, a Spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, ananthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group,a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a rubicenyl group, a coronenyl group, an ovalenyl group, athiophenyl group, a furanyl group, a carbazolyl group, an indolyl group,an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, a dibenzosilolyl group, and apyridinyl group.

The hole transport region may include at least one compound selectedfrom Compounds HT1 to HT39:

A thickness of the hole transport region may be in a range of about 100Å to about 10,000 Å, e.g., about 100 Å to about 1,000 Å. When the holetransport region includes at least one of a hole injection layer and ahole transport layer, the thickness of the hole injection layer may bein a range of about 100 Å to about 9,000 Å, e.g., about 100 Å to about1,000 Å, and the thickness of the hole transport layer may be in a rangeof about 50 Å to about 2,000 Å, e.g., about 100 Å to about 1,500 Å. Whenthe thicknesses of the hole transport region, the hole injection layerand the hole transport layer are within these ranges, satisfactory holetransporting characteristics may be obtained without a substantialincrease in driving voltage.

The emission auxiliary layer may increase light-emission efficiency bycompensating for an optical resonance distance according to thewavelength of light emitted by an emission layer, and the electronblocking layer may block the flow of electrons from an electrontransport region. The emission auxiliary layer and the electron blockinglayer may include the materials as described above.

The hole transport region may further include, in addition to thesematerials, a charge-generation material for the improvement ofconductive properties. The charge-generation material may behomogeneously or non-homogeneously dispersed in the hole transportregion.

The charge-generation material may be, e.g., a p-dopant.

In one or more embodiments, a lowest unoccupied molecular orbital (LUMO)level of the p-dopant may be −3.5 eV or less.

The p-dopant may include at least one selected from a quinonederivative, a metal oxide, and a cyano group-containing compound.

For example, the p-dopant may include at least one selected from:

a quinone derivative, such as tetracyanoquinodimethane (TCNQ) and2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4-TCNQ);

a metal oxide, such as tungsten oxide or molybdenum oxide;

1,4,5,8,9,11-hexaazatriphenylene-hexacarbonitrile (HAT-CN); and

a compound represented by Formula 221 below:

In Formula 221,

R₂₂₁ to R₂₂₃ may each independently be selected from a substituted orunsubstituted C₃-C₁₀ cycloalkyl group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀cycloalkenyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀ arylgroup, a substituted or unsubstituted C₁-C₆₀ heteroaryl group, asubstituted or unsubstituted monovalent non-aromatic condensedpolycyclic group and a substituted or unsubstituted monovalentnon-aromatic condensed heteropolycyclic group, wherein at least one ofR₂₂₁ to R₂₂₃ may have at least one substituent selected from a cyanogroup, —F, —Cl, —Br, —I, a C₁-C₂₀ alkyl group substituted with —F, aC₁-C₂₀ alkyl group substituted with —Cl, a C₁-C₂₀ alkyl groupsubstituted with —Br, and a C₁-C₂₀ alkyl group substituted with —I.

When the organic light-emitting device 10 is a full color organiclight-emitting device, the emission layer may be patterned into a redemission layer, a green emission layer, or a blue emission layer,according to a sub-pixel. In one or more embodiments, the emission layermay have a stacked structure of two or more layers selected from a redemission layer, a green emission layer, and a blue emission layer, inwhich the two or more layers contact each other or are separated fromeach other. In one or more embodiments, the emission layer may includetwo or more materials selected from a red-light emission material, agreen-light emission material, and a blue-light emission material, inwhich the two or more materials are mixed with each other in a singlelayer to emit white light.

The emission layer may include a host and a dopant. The dopant mayinclude at least one selected from a phosphorescent dopant and afluorescent dopant.

An amount of the dopant in the emission layer may be, e.g., in a rangeof about 0.01 to about 15 parts by weight based on 100 parts by weightof the host.

A thickness of the emission layer may be in a range of about 100 Å toabout 1,000 Å, e.g., about 200 Å to about 600 Å. When the thickness ofthe emission layer is within this range, excellent light-emissioncharacteristics may be obtained without a substantial increase indriving voltage.

In one or more embodiments, the host may include a compound representedby Formula 301 below.

<Formula 301>[Ar₃₀₁]_(xb11)-[(L₃₀₁)_(xb1)-R₃₀₁]_(xb21).

In Formula 301,

Ar₃₀₁ may be a substituted or unsubstituted C₅-C₆₀ carbocyclic group ora substituted or unsubstituted C₁-C₆₀ heterocyclic group,

xb11 may be 1, 2, or 3,

L₃₀₁ may be selected from a substituted or unsubstituted C₃-C₁₀cycloalkylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkylene group, a substituted or unsubstituted C₃-C₁₀cycloalkenylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenylene group, a substituted or unsubstituted C₆-C₆₀arylene group, a substituted or unsubstituted C₁-C₆₀ heteroarylenegroup, a substituted or unsubstituted divalent non-aromatic condensedpolycyclic group, and a substituted or unsubstituted divalentnon-aromatic condensed heteropolycyclic group;

xb1 may be an integer from 0 to 5,

R₃₀₁ may be selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group,a cyano group, a nitro group, an amidino group, a hydrazino group, ahydrazono group, a substituted or unsubstituted C₁-C₆₀ alkyl group, asubstituted or unsubstituted C₂-C₆₀ alkenyl group, a substituted orunsubstituted C₂-C₆₀ alkynyl group, a substituted or unsubstitutedC₁-C₆₀ alkoxy group, a substituted or unsubstituted C₃-C₁₀ cycloalkylgroup, a substituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, asubstituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted orunsubstituted C₁-C₁₀ heterocycloalkenyl group, a substituted orunsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₆-C₆₀aryloxy group, a substituted or unsubstituted C₆-C₆₀ arylthio group, asubstituted or unsubstituted C₁-C₆₀ heteroaryl group, a substituted orunsubstituted monovalent non-aromatic condensed polycyclic group, asubstituted or unsubstituted monovalent non-aromatic condensedheteropolycyclic group, —Si(Q₃₀₁)(Q₃₀₂)(Q₃₀₃), —N(Q₃₀₁)(Q₃₀₂),—B(Q₃₀₁)(Q₃₀₂), —C(═O)(Q₃₀₁), —S(═O)₂(Q₃₀₁), and —P(═O)(Q₃₀₁)(Q₃₀₂),

xb21 may be an integer from 1 to 5,

Q₃₀₁ to Q₃₀₃ may each independently be selected from a C₁-C₁₀ alkylgroup, a C₁-C₁₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, and a naphthyl group.

In one or more embodiments, Ar₃₀₁ in Formula 301 may be selected from:

a naphthalene group, a fluorene group, a spiro-bifluorene group, abenzofluorene group, a dibenzofluorene group, a phenalene group, aphenanthrene group, an anthracene group, a fluoranthene group, atriphenylene group, a pyrene group, a chrysene group, a naphthacenegroup, a picene group, a perylene group, a pentaphene group, anindenoanthracene group, a dibenzofuran group, and a dibenzothiophenegroup; and

a naphthalene group, a fluorene group, a spiro-bifluorene group, abenzofluorene group, a dibenzofluorene group, a phenalene group, aphenanthrene group, an anthracene group, a fluoranthene group, atriphenylene group, a pyrene group, a chrysene group, a naphthacenegroup, a picene group, a perylene group, a pentaphene group, anindenoanthracene group, a dibenzofuran group, and a dibenzothiophenegroup, each substituted with at least one selected from deuterium, —F,—Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidinogroup, a hydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, aC₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, a terphenylgroup, a naphthyl group, —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂),—C(═O)(Q₃₁), —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂),

wherein Q₃1 to Q₃₃ may each independently be selected from a C₁-C₁₀alkyl group, a C₁-C₁₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, and a naphthyl group.

When xb11 in Formula 301 is two or more, two or more Ar₃₀₁(s) may belinked via a single bond.

In one or more embodiments, the compound represented by Formula 301 maybe represented by Formulae 301-1 or 301-2:

In Formulae 301-1 to 301-2,

A₃₀₁ to A₃₀₄ may each independently be selected from a benzene group, anaphthalene group, a phenanthrene group, a fluoranthene group, atriphenylene group, a pyrene group, a chrysene group, a pyridine group,a pyrimidine group, an indene group, a fluorene group, aspiro-bifluorene group, a benzofluorene group, a dibenzofluorene group,an indole group, a carbazole group, a benzocarbazole group, adibenzocarbazole group, a furan group, a benzofuran group, adibenzofuran group, a naphthofuran group, a benzonaphthofuran group, adinaphthofuran group, a thiophene group, a benzothiophene group, adibenzothiophene group, a naphthothiophene group, abenzonaphthothiophene group, and a dinaphthothiophene group,

X₃₀₁ may be O, S, or N-[(L₃₀₄)_(xb4)-R₃₀₄],

R₃₁₁ to R₃₁₄ may each independently be selected from hydrogen,deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, a naphthyl group —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂),—B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁), —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂),

xb22 and xb23 may each independently be 0, 1, or 2,

L₃₀₁, xb1, R₃₀₁, and Q₃₁ to Q₃₃ may be the same as described above,

L₃₀₂ to L₃₀₄ may each independently be the same as described inconnection with

L₃₀₁,

xb2 to xb4 may each independently be the same as described in connectionwith xb1, and

R₃₀₂ to R₃₀₄ may each independently be the same as described inconnection with R₃₀₁.

For example, L₃₀₁ to L₃₀₄ in Formulae 301, 301-1, and 301-2 may eachindependently be selected from:

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a fluoranthenylene group, a triphenylenylene group, a pyrenylenegroup, a chrysenylene group, a perylenylene group, a pentaphenylenegroup, a hexacenylene group, a pentacenylene group, a thiophenylenegroup, a furanylene group, a carbazolylene group, an indolylene group,an isoindolylene group, a benzofuranylene group, a benzothiophenylenegroup, a dibenzofuranylene group, a dibenzothiophenylene group, abenzocarbazolylene group, a dibenzocarbazolylene group, adibenzosilolylene group, a pyridinylene group, an imidazolylene group, apyrazolylene group, a thiazolylene group, an isothiazolylene group, anoxazolylene group, an isoxazolylene group, a thiadiazolylene group, anoxadiazolylene group, a pyrazinylene group, a pyrimidinylene group, apyridazinylene group, a triazinylene group, a quinolinylene group, anisoquinolinylene group, a benzoquinolinylene group, a phthalazinylenegroup, a naphthyridinylene group, a quinoxalinylene group, aquinazolinylene group, a cinnolinylene group, a phenanthridinylenegroup, an acridinylene group, a phenanthrolinylene group, aphenazinylene group, a benzimidazolylene group, an isobenzothiazolylenegroup, a benzoxazolylene group, an isobenzoxazolylene group, atriazolylene group, a tetrazolylene group, an imidazopyridinylene group,an imidazopyrimidinylene group, and an azacarbazolylene group; and

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a fluoranthenylene group, a triphenylenylene group, a pyrenylenegroup, a chrysenylene group, a perylenylene group, a pentaphenylenegroup, a hexacenylene group, a pentacenylene group, a thiophenylenegroup, a furanylene group, a carbazolylene group, an indolylene group,an isoindolylene group, a benzofuranylene group, a benzothiophenylenegroup, a dibenzofuranylene group, a dibenzothiophenylene group, abenzocarbazolylene group, a dibenzocarbazolylene group, adibenzosilolylene group, a pyridinylene group, an imidazolylene group, apyrazolylene group, a thiazolylene group, an isothiazolylene group, anoxazolylene group, an isoxazolylene group, a thiadiazolylene group, anoxadiazolylene group, a pyrazinylene group, a pyrimidinylene group, apyridazinylene group, a triazinylene group, a quinolinylene group, anisoquinolinylene group, a benzoquinolinylene group, a phthalazinylenegroup, a naphthyridinylene group, a quinoxalinylene group, aquinazolinylene group, a cinnolinylene group, a phenanthridinylenegroup, an acridinylene group, a phenanthrolinylene group, aphenazinylene group, a benzimidazolylene group, an isobenzothiazolylenegroup, a benzoxazolylene group, an isobenzoxazolylene group, atriazolylene group, a tetrazolylene group, an imidazopyridinylene group,an imidazopyrimidinylene group, and an azacarbazolylene group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, anaphthyl group, a fluorenyl group, a spiro-bifluorenyl group, abenzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group,an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a perylenyl group, a pentaphenylgroup, a hexacenyl group, a pentacenyl group, a thiophenyl group, afuranyl group, a carbazolyl group, an indolyl group, an isoindolylgroup, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranylgroup, a dibenzothiophenyl group, a benzocarbazolyl group, adibenzocarbazolyl group, a dibenzosilolyl group, a pyridinyl group, animidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolylgroup, an oxazolyl group, an isoxazolyl group, a thiadiazolyl group, anoxadiazolyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a triazinyl group, a quinolinyl group, an isoquinolinyl group, abenzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, aquinoxalinyl group, a quinazolinyl group, a cinnolinyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, aphenazinyl group, a benzimidazolyl group, an isobenzothiazolyl group, abenzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, atetrazolyl group, an imidazopyridinyl group, an imidazopyrimidinylgroup, an aza carbazolyl group, —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂),—B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁), —S(═O)₂(Q₃₁) and —P(═O)(Q₃₁)(Q₃₂),

wherein Q₃₁ to Q₃₃ may be the same as described above.

In one or more embodiments, R₃₀₁ to R₃₀₄ in Formulae 301, 301-1, and301-2 may each independently be selected from:

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a Spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, an imidazolyl group, apyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group,a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a phthalazinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a cinnolinyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolylgroup, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group,an imidazopyridinyl group, an imidazopyrimidinyl group, and anazacarbazolyl group; and

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, an imidazolyl group, apyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group,a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a phthalazinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a cinnolinyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolylgroup, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group,an imidazopyridinyl group, an imidazopyrimidinyl group, and anazacarbazolyl group, each substituted with at least one selected fromdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, a naphthyl group, a fluorenyl group, aspiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenylgroup, a phenanthrenyl group, an anthracenyl group, a fluoranthenylgroup, a triphenylenyl group, a pyrenyl group, a chrysenyl group, aperylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a thiophenyl group, a furanyl group, a carbazolyl group, anindolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, an imidazolyl group, apyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group,a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a phthalazinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a cinnolinyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolylgroup, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group,an imidazopyridinyl group, an imidazopyrimidinyl group, an azacarbazolyl group, —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃1)(Q₃₂),—C(═O)(Q₃₁), —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂); and

Q₃₁ to Q₃₃ may be the same as described above.

In one or more embodiments, the host may include an alkaline-earth metalcomplex. For example, the host may be selected from a Be complex (forexample, Compound H55), an Mg complex, and a Zn complex.

The host may include at least one selected from9,10-di(2-naphthyl)anthracene (ADN),2-methyl-9,10-bis(naphthalen-2-yl)anthracene (MADN),9,10-di-(2-naphthyl)-2-t-butyl-anthracene (TBADN), a4,4′-bis(N-carbazolyl)-1,1′-biphenyl (CBP), 1,3-di-9-carbazolylbenzene(mCP), 1,3,5-tri(carbazol-9-yl)benzene (TCP), and Compounds H1 to H55:

The phosphorescent dopant may include an organometallic complexrepresented by Formula 401 below:

In Formulae 401 and 402,

M may be selected from iridium (Ir), platinum (Pt), palladium (Pd),osmium (Os), titanium (Ti), zirconium (Zr), hafnium (Hf), europium (Eu),terbium (Tb), rhodium (Rh), and thulium (Tm),

L₄₀₁ may be selected from ligands represented by Formula 402, and xc1may be 1, 2, or 3, wherein, when xcl is two or more, two or more L₄₀₁(s)may be identical to or different from each other,

L₄₀₂ may be an organic ligand, and xc2 may be an integer from 0 to 4,wherein, when xc2 is two or more, two or more L₄₀₂(s) may be identicalto or different from each other,

X₄₀₁ to X₄₀₄ may each independently be nitrogen or carbon,

X₄₀₁ and X₄₀₃ may be linked via a single bond or a double bond, and X₄₀₂and X₄₀₄ may be linked via a single bond or a double bond,

A₄₀₁ and A₄₀₂ may each independently be selected from a C₅-C₆₀carbocyclic group or a C₁-C₆₀ heterocyclic group,

X₄₀₅ may be a single bond, *—O—*′, *—C(═O)—*I, *—N(Q₄₁₁)—*′,*—C(Q₄₁₁)(Q₄₁₂)-′, *—C(Q₄₁₁)=C(Q₄₁₂)-*′, *—C(Q₄₁₁)=′, or *═C(Q₄₁₁)=*′,wherein Q₄₁₁ and Q₄₁₂ may be hydrogen, deuterium, a C₁-C₂₀ alkyl group,a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, a terphenylgroup, or a naphthyl group,

X₄₀₆ may be a single bond, O, or S,

R₄₀₁ and R₄₀₂ may each independently be selected from hydrogen,deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, asubstituted or unsubstituted C₁-C₂₀ alkyl group, a substituted orunsubstituted C₁-C₂₀ alkoxy group, a substituted or unsubstituted C₃-C₁₀cycloalkyl group, a substituted or unsubstituted C₁-C₁₀ heterocycloalkylgroup, a substituted or unsubstituted C₃-C₁₀ cycloalkenyl group, asubstituted or unsubstituted C₁-C₁₀ heterocycloalkenyl group, asubstituted or unsubstituted C₆-C₆₀ aryl group, a substituted orunsubstituted C₆-C₆₀ aryloxy group, a substituted or unsubstitutedC₆-C₆₀ arylthio group, a substituted or unsubstituted C₁-C₆₀ heteroarylgroup, a substituted or unsubstituted monovalent non-aromatic condensedpolycyclic group and a substituted or unsubstituted monovalentnon-aromatic condensed heteropolycyclic group, —Si(Q₄₀₁)(Q₄₀₂)(Q₄₀₃),—N(Q₄₀(Q₄₀₂), —B(Q₄₀₁)(Q₄₀₂), —C(═O)(Q₄₀₁), —S(═O)₂(Q₄₀₁), and—P(=O)(Q₄₀₁)(Q₄₀₂), wherein Q₄₀₁ to Q₄₀₃ may each independently beselected from a C₁-C₁₀ alkyl group, a C₁-C₁₀ alkoxy group, a C₆-C₂₀ arylgroup, and a C₁-C₂₀ heteroaryl group,

xc11 and xc12 may each independently be an integer from 0 to 10, and

* and *′ in Formula 402 each indicate a binding site to M in Formula401.

In one or more embodiments, A₄₀₁ and A₄₀₂ in Formula 402 may eachindependently be selected from a benzene group, a naphthalene group, afluorene group, a spiro-bifluorene group, an indene group, a pyrrolegroup, a thiophene group, a furan group, an imidazole group, a pyrazolegroup, a thiazole group, an isothiazole group, an oxazole group, anisoxazole group, a pyridine group, a pyrazine group, a pyrimidine group,a pyridazine group, a quinoline group, an isoquinoline group, abenzoquinoline group, a quinoxaline group, a quinazoline group, acarbazole group, a benzimidazole group, a benzofuran group, abenzothiophene group, an isobenzothiophene group, a benzoxazole group,an isobenzoxazole group, a triazole group, a tetrazole group, anoxadiazole group, a triazine group, a dibenzofuran group, and adibenzothiophene group.

In one or more embodiments, in Formula 402, i) X₄₀₁ may be nitrogen, andX₄₀₂ may be carbon, or ii) X₄₀₁ and X₄₀₂ may each be nitrogen at thesame time.

In one or more embodiments, R₄₀₁ and R₄₀₂ in Formula 402 may eachindependently be selected from:

hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, an amidino group, a hydrazino group, a hydrazono group, aC₁-C₂₀ alkyl group, and a C₁-C₂₀ alkoxy group;

a C₁-C₂₀ alkyl group and a C₁-C₂₀ alkoxy group, each substituted with atleast one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, acyano group, a nitro group, an amidino group, a hydrazino group, ahydrazono group, a phenyl group, a naphthyl group, a cyclopentyl group,a cyclohexyl group, an adamantanyl group, a norbornanyl group, and anorbornenyl group;

a cyclopentyl group, a cyclohexyl group, an adamantanyl group, anorbornanyl group, a norbornenyl group, a phenyl group, a biphenylgroup, a terphenyl group, a naphthyl group, a fluorenyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a triazinyl group, a quinolinyl group, an isoquinolinyl group, aquinoxalinyl group, a quinazolinyl group, a carbazolyl group, adibenzofuranyl group, and a dibenzothiophenyl group;

a cyclopentyl group, a cyclohexyl group, an adamantanyl group, anorbornanyl group, a norbornenyl group a phenyl group, a biphenyl group,a terphenyl group, a naphthyl group, a fluorenyl group, a pyridinylgroup, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, atriazinyl group, a quinolinyl group, an isoquinolinyl group, aquinoxalinyl group, a quinazolinyl group, a carbazolyl group, adibenzofuranyl group, and a dibenzothiophenyl group, each substitutedwith at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxylgroup, a cyano group, a nitro group, an amidino group, a hydrazinogroup, a hydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, acyclopentyl group, a cyclohexyl group, an adamantanyl group, anorbornanyl group, a norbornenyl group, a phenyl group, a biphenylgroup, a terphenyl group, a naphthyl group, a fluorenyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a triazinyl group, a quinolinyl group, an isoquinolinyl group, aquinoxalinyl group, a quinazolinyl group, a carbazolyl group, adibenzofuranyl group, and a dibenzothiophenyl group; and

—Si(Q₄₀₁)(Q₄₀₂)(Q₄₀₃), —N(Q₄₀₁)(Q₄₀₂), —B(Q₄₀₁)(Q₄₀₂), —C(═O)(Q₄₀₁),—S(═O)₂(Q₄₀₁), and —P(═O)(Q₄₀₁)(Q₄₀₂),

wherein Q₄₀₁ to Q₄₀₃ may each independently be selected from a C₁-C₁₀alkyl group, a C₁-C₁₀ alkoxy group, a phenyl group, a biphenyl group,and a naphthyl group.

In one or more embodiments, when xcl in Formula 401 is two or more, twoA₄₀₁(s) in two or more L₄₀₁(s) may optionally be linked to each othervia X₄₀₇, which is a linking group, or two A₄₀₂(s) in two or moreL₄₀₁(s) may optionally be linked to each other via X₄₀₈, which is alinking group (see Compounds PD1 to PD4 and PD7). X₄₀₇ and X₄₀₈ may eachindependently be a single bond, *—O—*′, *—S—*′, *—C(═O)—*′,*—N(Q₄₁₃)-*′, *—C(Q₄₁₃)(Q₄₁₄)-*′, or *—C(Q₄₁₃)=C(Q₄₁₄)-*′ (wherein Q₄₁₃and Q₄₁₄ may each independently be hydrogen, deuterium, a C₁-C₂₀ alkylgroup, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, or a naphthyl group).

L₄₀₂ in Formula 401 may be a monovalent, divalent, or trivalent organicligand.

For example, L₄₀₂ may be selected from halogen, diketone (for example,acetylacetonate), carboxylic acid (for example, picolinate), —C(═O),isonitrile, —CN, and phosphorus (for example, phosphine, or phosphite).

In one or more embodiments, the phosphorescent dopant may be selectedfrom, for example, Compounds PD1 to PD25:

The fluorescent dopant may include an arylamine compound or astyrylamine compound.

The fluorescent dopant may include a compound represented by Formula 501below.

In Formula 501,

Ar₅₀₁ may be a substituted or unsubstituted C₅-C₆₀ carbocyclic group ora substituted or unsubstituted C₁-C₆₀ heterocyclic group,

L₅₀₁ to L₅₀₃ may each independently be selected from a substituted orunsubstituted C₃-C₁₀ cycloalkylene group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkylene group, a substituted or unsubstituted C₃-C₁₀cycloalkenylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenylene group, a substituted or unsubstituted C₆-C₆₀arylene group, a substituted or unsubstituted C ₁-C₆₀ heteroarylenegroup, a substituted or unsubstituted divalent non-aromatic condensedpolycyclic group, and a substituted or unsubstituted divalentnon-aromatic condensed heteropolycyclic group,

xd1 to xd3 may each independently be an integer of 0 to 3;

R₅₀₁ and R₅₀₂ may each independently be selected from a substituted orunsubstituted C₃-C₁₀ cycloalkyl group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀cycloalkenyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀ arylgroup, a substituted or unsubstituted C₆-C₆₀ aryloxy group, asubstituted or unsubstituted C₆-C₆₀ arylthio group, a substituted orunsubstituted C₁-C₆₀ heteroaryl group, a substituted or unsubstitutedmonovalent non-aromatic condensed polycyclic group, and a substituted orunsubstituted monovalent non-aromatic condensed heteropolycyclic group,and

xd4 may be an integer of 1 to 6.

In one or more embodiments, Ar₅₀₁ in Formula 501 may be selected from:

a naphthalene group, a heptalene group, a fluorene group, aspiro-bifluorene group, a benzofluorene group, a dibenzofluorene group,a phenalene group, a phenanthrene group, an anthracene group, afluoranthene group, a triphenylene group, a pyrene group, a chrysenegroup, a naphthacene group, a picene group, a perylene group, apentaphene group, an indenoanthracene group, and an indenophenanthrenegroup; and

a naphthalene group, a heptalene group, a fluorene group, aspiro-bifluorene group, a benzofluorene group, a dibenzofluorene group,a phenalene group, a phenanthrene group, an anthracene group, afluoranthene group, a triphenylene group, a pyrene group, a chrysenegroup, a naphthacene group, a picene group, a perylene group, apentaphene group, an indenoanthracene group, and an indenophenanthrenegroup, each substituted with at least one selected from deuterium, —F,—Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidinogroup, a hydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, a terphenyl group,and a naphthyl group.

In one or more embodiments, L₅₀₁ to L₅₀₃ in Formula 501 may eachindependently be selected from:

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a fluoranthenylene group, a triphenylenylene group, a pyrenylenegroup, a chrysenylene group, a perylenylene group, a pentaphenylenegroup, a hexacenylene group, a pentacenylene group, a thiophenylenegroup, a furanylene group, a carbazolylene group, an indolylene group,an isoindolylene group, a benzofuranylene group, a benzothiophenylenegroup, a dibenzofuranylene group, a dibenzothiophenylene group, abenzocarbazolylene group, a dibenzocarbazolylene group,dibenzosilolylene group, and a pyridinylene group; and

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a fluoranthenylene group, a triphenylenylene group, a pyrenylenegroup, a chrysenylene group, a perylenylene group, a pentaphenylenegroup, a hexacenylene group, a pentacenylene group, a thiophenylenegroup, a furanylene group, a carbazolylene group, an indolylene group,an isoindolylene group, a benzofuranylene group, a benzothiophenylenegroup, a dibenzofuranylene group, a dibenzothiophenylene group, abenzocarbazolylene group, a dibenzocarbazolylene group,dibenzosilolylene group, and a pyridinylene group, each substituted withat least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxylgroup, a cyano group, a nitro group, an amidino group, a hydrazinogroup, a hydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, aphenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, and a pyridinyl group.

In one or more embodiments, R₅₀₁ and R₅₀₁ in Formula 502 may eachindependently be selected from:

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, and a pyridinyl group; and

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, and a pyridinyl group, each substituted with atleast one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, acyano group, a nitro group, an amidino group, a hydrazino group, ahydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenylgroup, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, and —Si(Q₃₁)(Q₃₂)(Q₃₃),

wherein Q₃₁ to Q₃₃ may each be selected from a C₁-C₁₀ alkyl group, aC₁-C₁₀ alkoxy group, a phenyl group, a biphenyl group, a terphenylgroup, and a naphthyl group.

In one or more embodiments, xd4 in Formula 501 may be 2.

For example, the fluorescent dopant may be selected from Compounds FD1to FD22:

In one or more embodiments, the fluorescent dopant may be selected fromthe following compounds.

The electron transport region may have i) a single-layered structureincluding a single layer including a single material, ii) asingle-layered structure including a single layer including a pluralityof different materials, or iii) a multi-layered structure having aplurality of layers including a plurality of different materials.

The electron transport region may include at least one selected from abuffer layer, a hole blocking layer, an electron control layer, anelectron transport layer, and an electron injection layer.

For example, the electron transport region may have an electrontransport layer/electron injection layer structure, a hole blockinglayer/electron transport layer/electron injection layer structure, anelectron control layer/electron transport layer/electron injection layerstructure, or a buffer layer/electron transport layer/electron injectionlayer structure, wherein, for each structure, constituting layers aresequentially stacked from an emission layer.

The electron transport region (for example, a buffer layer, a holeblocking layer, an electron control layer, or an electron transportlayer in the electron transport region) may include a metal-freecompound containing at least one π electron-depleted nitrogen-containingring.

The “π electron-depleted nitrogen-containing ring” indicates a C₁-C₆₀heterocyclic group having at least one *—N═*′ moiety as a ring-formingmoiety.

For example, the “π electron-depleted nitrogen-containing ring” may bei) a 5-membered to 7-membered hetero monocyclic group having at leastone *—N′*′ moiety, ii) a heteropoly cyclic group in which two or more5-membered to 7-membered hetero monocyclic groups each having at leastone *—N═*′ moiety are condensed with each other, or iii) a heteropolycyclic group in which at least one of 5-membered to 7-membered heteromonocyclic groups, each having at least one *—N═*′ moiety, is condensedwith at least one C₅-C₆₀ carbocyclic group.

Examples of the 7C electron-depleted nitrogen-containing ring include animidazole, a pyrazole, a thiazole, an isothiazole, an oxazole, anisoxazole, a pyridine, a pyrazine, a pyrimidine, a pyridazine, anindazole, a purine, a quinoline, an isoquinoline, a benzoquinoline, aphthalazine, a naphthyridine, a quinoxaline, a quinazoline, a cinnoline,a phenanthridine, an acridine, a phenanthroline, a phenazine, abenzimidazole, an isobenzothiazole, a benzoxazole, an isobenzoxazole, atriazole, a tetrazole, an oxadiazole, a triazine, a thiadiazole, animidazopyridine, an imidazopyrimidine, and an azacarbazole.

For example, the electron transport region may include a compoundrepresented by Formula 601:[Ar₆₀₁]_(xe11)-[(L₆₀₁)_(xe1)-R₆₀₁]_(xe21).   <Formula 601>

In Formula 601,

Ar₆₀₁ may be a substituted or unsubstituted C₅-C₆₀ carbocyclic group ora substituted or unsubstituted C₁-C₆₀ heterocyclic group,

xe11 may be 1, 2, or 3,

L₆₀₁ may be selected from a substituted or unsubstituted C₃-C₁₀cycloalkylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkylene group, a substituted or unsubstituted C₃-C₁₀cycloalkenylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenylene group, a substituted or unsubstituted C₆-C₆₀arylene group, a substituted or unsubstituted C₁-C₆₀ heteroarylenegroup, a substituted or unsubstituted divalent non-aromatic condensedpolycyclic group, and a substituted or unsubstituted divalentnon-aromatic condensed heteropolycyclic group;

xe1 may be an integer from 0 to 5,

R₆₀₁ may be selected from a substituted or unsubstituted C₃-C₁₀cycloalkyl group, a substituted or unsubstituted C₁-C₁₀ heterocycloalkylgroup, a substituted or unsubstituted C₃-C₁₀ cycloalkenyl group, asubstituted or unsubstituted C₁-C₁₀ heterocycloalkenyl group, asubstituted or unsubstituted C₆-C₆₀ aryl group, a substituted orunsubstituted C₆-C₆₀ aryloxy group, a substituted or unsubstitutedC₆-C₆₀ arylthio group, a substituted or unsubstituted C₁-C₆₀ heteroarylgroup, a substituted or unsubstituted monovalent non-aromatic condensedpolycyclic group, a substituted or unsubstituted monovalent non-aromaticcondensed heteropolycyclic group, —Si(Q_(6o1))(Q₆₀₂)(Q₆₀₃),—C(═O)(Q₆₀₁), —S(═O)₂(Q₆₀₁), and —P(═O)(Q₆₀₁)(Q₆₀₂),

Q₆₀₁ to Q₆₀₃ may each independently be a C₁-C₁₀ alkyl group, a C₁-C₁₀alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, or anaphthyl group, and

xe21 may be an integer from 1 to 5.

In one or more embodiments, at least one of Ar₆₀₁(s) in the number ofxe11 and/or at least one of R₆₀₁(s) in the number of xe21 may includethe π electron-depleted nitrogen-containing ring.

In one or more embodiments, ring Ar₆₀₁ in Formula 601 may be selectedfrom:

a benzene group, a naphthalene group, a fluorene group, aspiro-bifluorene group, a benzofluorene group, a dibenzofluorene group,a phenalene group, a phenanthrene group, an anthracene group, afluoranthene group, a triphenylene group, a pyrene group, a chrysenegroup, a naphthacene group, a picene group, a perylene group, apentaphene group, an indenoanthracene group, a dibenzofuran group, adibenzothiophene group, a carbazole group, an imidazole group, apyrazole group, a thiazole group, an isothiazole group, an oxazolegroup, an isoxazole group, a pyridine group, a pyrazine group, apyrimidine group, a pyridazine group, an indazole group, a purine group,a quinoline group, an isoquinoline group, a benzoquinoline group, aphthalazine group, naphthyridine group, a quinoxaline group, aquinazoline group, a cinnoline group, a phenanthridine group, anacridine group, a phenanthroline group, a phenazine group, abenzimidazole group, an iso-benzothiazole group, a benzoxazole group, anisobenzoxazole group, a triazole group, a tetrazole group, an oxadiazolegroup, a triazine group, thiadiazol group, an imidazopyridine group, animidazopyrimidine group, and an azacarbazole group; and

a benzene group, a naphthalene group, a fluorene group, aspiro-bifluorene group, a benzofluorene group, a dibenzofluorene group,a phenalene group, a phenanthrene group, an anthracene group, afluoranthene group, a triphenylene group, a pyrene group, a chrysenegroup, a naphthacene group, a picene group, a perylene group, apentaphene group, an indenoanthracene group, a dibenzofuran group, adibenzothiophene group, a carbazole group, an imidazole group, apyrazole group, a thiazole group, an isothiazole group, an oxazolegroup, an isoxazole group, a pyridine group, a pyrazine group, apyrimidine group, a pyridazine group, an indazole group, a purine group,a quinoline group, an isoquinoline group, a benzoquinoline group, aphthalazine group, naphthyridine group, a quinoxaline group, aquinazoline group, a cinnoline group, a phenanthridine group, anacridine group, a phenanthroline group, a phenazine group, abenzimidazole group, an iso-benzothiazole group, a benzoxazole group, anisobenzoxazole group, a triazole group, a tetrazole group, an oxadiazolegroup, a triazine group, thiadiazol group, an imidazopyridine group, animidazopyrimidine group, and an azacarbazole group, each substitutedwith at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxylgroup, a cyano group, a nitro group, an amidino group, a hydrazinogroup, a hydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, aphenyl group, a biphenyl group, a terphenyl group, a naphthyl group,—Si(Q₃₁)(Q₃₂)(Q₃₃), —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂),

wherein Q₃1 to Q₃₃ may each independently be selected from a C₁-C₁₀alkyl group, a C₁-C₁₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, and a naphthyl group.

When xe11 in Formula 601 is two or more, two or more Ar₆₀₁(s) may belinked to each other via a single bond.

In one or more embodiments, Ar₆₀₁ in Formula 601 may be an anthracenegroup.

In one or more embodiments, a compound represented by Formula 601 may berepresented by Formula 601-1:

In Formula 601-1,

X₆₁₄ may be N or C(R₆₁₄), X₆₁₅ may be N or C(R₆₁₅), X₆₁₆ may be N orC(R₆₁₆), and at least one selected from X₆₁₄ to X₆₁₆ may be N,

L₆₁₁ to L₆₁₃ may be each independently substantially the same asdescribed in connection with L₆₀₁,

xe611 to xe613 may be each independently substantially the same asdescribed in connection with xe1,

R₆₁₁ to R₆₁₃ may be each independently substantially the same asdescribed in connection with R₆₀₁, and

R₆₁₄ to R₆₁₆ may each independently be selected from hydrogen,deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C ₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, and a naphthyl group.

In one or more embodiments, L₆₀₁ and L₆₁₁ to L₆₁₃ in Formulae 601 and601-1 may each independently be selected from:

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a fluoranthenylene group, a triphenylenylene group, a pyrenylenegroup, a chrysenylene group, a perylenylene group, a pentaphenylenegroup, a hexacenylene group, a pentacenylene group, a thiophenylenegroup, a furanylene group, a carbazolylene group, an indolylene group,an isoindolylene group, a benzofuranylene group, a benzothiophenylenegroup, a dibenzofuranylene group, a dibenzothiophenylene group, abenzocarbazolylene group, a dibenzocarbazolylene group, adibenzosilolylene group, a pyridinylene group, an imidazolylene group, apyrazolylene group, a thiazolylene group, an isothiazolylene group, anoxazolylene group, an isoxazolylene group, a thiadiazolylene group, anoxadiazolylene group, a pyrazinylene group, a pyrimidinylene group, apyridazinylene group, a triazinylene group, a quinolinylene group, anisoquinolinylene group, a benzoquinolinylene group, a phthalazinylenegroup, a naphthyridinylene group, a quinoxalinylene group, aquinazolinylene group, a cinnolinylene group, a phenanthridinylenegroup, an acridinylene group, a phenanthrolinylene group, aphenazinylene group, a benzimidazolylene group, an isobenzothiazolylenegroup, a benzoxazolylene group, an isobenzoxazolylene group, atriazolylene group, a tetrazolylene group, an imidazopyridinylene group,an imidazopyrimidinylene group, and an azacarbazolylene group; and

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a fluoranthenylene group, a triphenylenylene group, a pyrenylenegroup, a chrysenylene group, a perylenylene group, a pentaphenylenegroup, a hexacenylene group, a pentacenylene group, a thiophenylenegroup, a furanylene group, a carbazolylene group, an indolylene group,an isoindolylene group, a benzofuranylene group, a benzothiophenylenegroup, a dibenzofuranylene group, a dibenzothiophenylene group, abenzocarbazolylene group, a dibenzocarbazolylene group, adibenzosilolylene group, a pyridinylene group, an imidazolylene group, apyrazolylene group, a thiazolylene group, an isothiazolylene group, anoxazolylene group, an isoxazolylene group, a thiadiazolylene group, anoxadiazolylene group, a pyrazinylene group, a pyrimidinylene group, apyridazinylene group, a triazinylene group, a quinolinylene group, anisoquinolinylene group, a benzoquinolinylene group, a phthalazinylenegroup, a naphthyridinylene group, a quinoxalinylene group, aquinazolinylene group, a cinnolinylene group, a phenanthridinylenegroup, an acridinylene group, a phenanthrolinylene group, aphenazinylene group, a benzimidazolylene group, an isobenzothiazolylenegroup, a benzoxazolylene group, an isobenzoxazolylene group, atriazolylene group, a tetrazolylene group, an imidazopyridinylene group,an imidazopyrimidinylene group, and an azacarbazolylene group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, anaphthyl group, a fluorenyl group, a spiro-bifluorenyl group, abenzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group,an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a perylenyl group, a pentaphenylgroup, a hexacenyl group, a pentacenyl group, a thiophenyl group, afuranyl group, a carbazolyl group, an indolyl group, an isoindolylgroup, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranylgroup, a dibenzothiophenyl group, a benzocarbazolyl group, adibenzocarbazolyl group, a dibenzosilolyl group, a pyridinyl group, animidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolylgroup, an oxazolyl group, an isoxazolyl group, a thiadiazolyl group, anoxadiazolyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a triazinyl group, a quinolinyl group, an isoquinolinyl group, abenzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, aquinoxalinyl group, a quinazolinyl group, a cinnolinyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, aphenazinyl group, a benzimidazolyl group, an isobenzothiazolyl group, abenzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, atetrazolyl group, an imidazopyridinyl group, an imidazopyrimidinylgroup, and an azacarbazolyl group.

In one or more embodiments, xe1 and xe611 to xe613 in Formulae 601 and601-1 may each independently be 0, 1, or 2.

In one or more embodiments, R₆₀₁ and R₆₁₁ to R₆₁₃ in Formula 601 and601-1 may each independently be selected from:

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, an imidazolyl group, apyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group,a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a phthalazinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a cinnolinyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolylgroup, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group,an imidazopyridinyl group, an imidazopyrimidinyl group, and anazacarbazolyl group; and

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, an imidazolyl group, apyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group,a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a phthalazinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a cinnolinyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolylgroup, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group,an imidazopyridinyl group, an imidazopyrimidinyl group, and anazacarbazolyl group, each substituted with at least one selected fromdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, a naphthyl group, a fluorenyl group, aspiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenylgroup, a phenanthrenyl group, an anthracenyl group, a fluoranthenylgroup, a triphenylenyl group, a pyrenyl group, a chrysenyl group, aperylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a thiophenyl group, a furanyl group, a carbazolyl group, anindolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, an imidazolyl group, apyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group,a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a phthalazinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a cinnolinyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolylgroup, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group,an imidazopyridinyl group, an imidazopyrimidinyl group, and anazacarbazolyl group; and

—S(═O)₂(Q₆₀₁) ,and —P(═O)(Q₆₀₁)(Q₆₀₂),

wherein Q₆₀₁ and Q₆₀₂ are substantially the same as described above.

The electron transport region may include at least one compound selectedfrom Compounds ET1 to ET36:

In one or more embodiments, the electron transport region may include atleast one selected from 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline(BCP), 4,7-dphenyl-1,10-phenanthroline (Bphen), Alq₃, BAlq,3-(biphenyl-4-yl)-5-(4-tert-butylphenyl)-4-phenyl-4H-1,2,4-triazole(TAZ), and NTAZ:

The thickness of the buffer layer, the hole blocking layer, or theelectron controlling layer may each independently be in a range of about20 Å to about 1,000 Å, e.g., about 30 Å to about 300 Å. When thethicknesses of the buffer layer, the hole blocking layer, and theelectron control layer are within these ranges, the electron blockinglayer may have excellent electron blocking characteristics or electroncontrol characteristics without a substantial increase in drivingvoltage.

A thickness of the electron transport layer may be in a range of about100 Å to about 1,000 Å, e.g., about 150 Å to about 500 Å. When thethickness of the electron transport layer is within the range describedabove, the electron transport layer may have satisfactory electrontransport characteristics without a substantial increase in drivingvoltage.

The electron transport region (for example, the electron transport layerin the electron transport region) may further include, in addition tothe materials described above, a metal-containing material.

The metal-containing material may include at least one selected from analkali metal complex and an alkaline earth-metal complex. The alkalimetal complex may include a metal ion selected from an Li ion, a Na ion,a K ion, a Rb ion, and a Cs ion, and the alkaline earth-metal complexmay include a metal ion selected from a Be ion, a Mg ion, a Ca ion, anSr ion, and a Ba ion. A ligand coordinated with the metal ion of thealkali metal complex or the alkaline earth-metal complex may be selectedfrom a hydroxy quinoline, a hydroxy isoquinoline, a hydroxybenzoquinoline, a hydroxy acridine, a hydroxy phenanthridine, a hydroxyphenylan oxazole, a hydroxy phenylthiazole, a hydroxydiphenyloxadiazole, a hydroxy diphenylthiadiazole, a hydroxyphenylpyridine, a hydroxy phenylbenzimidazole, a hydroxyphenylbenzothiazole, a bipyridine, a phenanthroline, and acyclopentadiene.

For example, the metal-containing material may include a Li complex. TheLi complex may include, e.g., Compound ET-D1 (lithium quinolate, LiQ) orET-D2:

The electron transport region may include an electron injection layerthat facilitates injection of electrons from the second electrode 190.The electron injection layer may directly contact the second electrode190.

The electron injection layer may have i) a single-layered structureincluding a single layer including a single material, ii) asingle-layered structure including a single layer including a pluralityof different materials, or iii) a multi-layered structure having aplurality of layers including a plurality of different materials.

The electron injection layer may include alkali metal, alkaline earthmetal, rare-earth metal, an alkali metal compound, an alkalineearth-metal compound, a rare-earth metal compound, an alkali metalcomplex, an alkaline earth-metal complex, a rare-earth metal complex, orany combinations thereof.

The alkali metal may be selected from Li, Na, K, Rb, and Cs. In one ormore embodiments, the alkali metal may be Li, Na, or Cs. In one or moreembodiments, the alkali metal may be Li or Cs.

The alkaline earth metal may be selected from Mg, Ca, Sr, and Ba.

The rare-earth metal may be selected from Sc, Y, Ce, Tb, Yb, and Gd.

The alkali metal compound, the alkaline earth-metal compound, and therare-earth metal compound may be selected from oxides and halides (forexample, fluorides, chlorides, bromides, or iodides) of the alkalimetal, the alkaline earth-metal, and the rare-earth metal.

The alkali metal compound may be selected from alkali metal oxides, suchas Li₂O, Cs₂O, or K₂O, and alkali metal halides, such as LiF, NaF, CsF,KF, LiI, NaI, CsI, KI, or RbI. In one or more embodiments, the alkalimetal compound may be selected from LiF, Li₂O, NaF, LiI, NaI, CsI, andKI.

The alkaline earth-metal compound may be selected from alkalineearth-metal compounds, such as BaO, SrO, CaO, Ba_(x)Sr_(1-x)O (0<x<l),or Ba_(x)Ca_(1-x)O(0<x<1). In one or more embodiments, the alkalineearth-metal compound may be selected from BaO, SrO, and CaO.

The rare-earth metal compound may be selected from YbF₃, ScF₃, ScO₃,Y₂O₃, Ce₂O₃, GdF₃, and TbF₃. In one or more embodiments, the rare-earthmetal compound may be selected from YbF₃, ScF₃, TbF₃, YbI₃, ScI₃, andTbI₃.

The alkali metal complex, the alkaline earth-metal complex, and therare-earth metal complex may include an ion of alkali metal, alkalineearth-metal, and rare-earth metal as described above, and a ligandcoordinated with a metal ion of the alkali metal complex, the alkalineearth-metal complex, and the rare-earth metal complex may eachindependently be selected from hydroxy quinoline, hydroxy isoquinoline,hydroxy benzoquinoline, hydroxy acridine, hydroxy phenanthridine,hydroxy phenylan oxazole, hydroxy phenylthiazole, hydroxy diphenylanoxadiazole, hydroxy diphenylthiadiazol, hydroxy phenylpyridine, hydroxyphenylbenzimidazole, hydroxy phenylbenzothiazole, bipyridine,phenanthroline, and cyclopentadiene.

The electron injection layer may consist of alkali metal, alkaline earthmetal, rare-earth metal, an alkali metal compound, an alkalineearth-metal compound, a rare-earth metal compound, an alkali metalcomplex, an alkaline earth-metal complex, a rare-earth metal complex, orany combinations thereof, as described above. In one or moreembodiments, the electron injection layer may further include an organicmaterial. When the electron injection layer further includes an organicmaterial, alkali metal, alkaline earth metal, rare-earth metal, analkali metal compound, an alkaline earth-metal compound, a rare-earthmetal compound, an alkali metal complex, an alkaline earth-metalcomplex, a rare-earth metal complex, or any combinations thereof may behomogeneously or non-homogeneously dispersed in a matrix including theorganic material.

A thickness of the electron injection layer may be in a range of about 1Å to about 100 Å, e.g., about 3 Å to about 90 Å. When the thickness ofthe electron injection layer is within the range described above, theelectron injection layer may have satisfactory electron injectioncharacteristics without a substantial increase in driving voltage.

The second electrode 190 may be disposed on the organic layer 150 havingsuch a structure. The second electrode 190 may be a cathode that is anelectron injection electrode, and in this regard, a material for formingthe second electrode 190 may be a material having a low work function,and such a material may be metal, alloy, an electrically conductivecompound, or a combination thereof.

The second electrode 190 may include at least one selected from lithium(Li), silver (Si), magnesium (Mg), aluminum (Al), aluminum-lithium(Al—Li), calcium (Ca), magnesium-indium (Mg—In), magnesium-silver(Mg—Ag), ITO, and IZO. The second electrode 190 may be a transmissiveelectrode, a semi-transmissive electrode, or a reflective electrode.

The second electrode 190 may have a single-layered structure, or amulti-layered structure including two or more layers.

Hereinbefore, the organic light-emitting device has been described withreference to FIG. 1.

Layers constituting the hole transport region, an emission layer, andlayers constituting the electron transport region may be formed in acertain region by using one or more suitable methods selected fromvacuum deposition, spin coating, casting, langmuir-blodgett (LB)deposition, ink-jet printing, laser-printing, and laser-induced thermalimaging.

When the respective layers of the hole transport region, the emissionlayer, and the respective layers of the electron transport region areformed by deposition, the deposition may be performed at a depositiontemperature of about 100 to about 500° C., at a vacuum degree of about10⁻⁸ to about 10⁻³ torr, and at a deposition rate of about 0.01 to about100 Å/sec by taking into account a material for forming a layer to bedeposited, and the structure of a layer to be formed.

When layers constituting the hole transport region, an emission layer,and layers constituting the electron transport region are formed by spincoating, the spin coating may be performed at a coating speed of about2,000 rpm to about 5,000 rpm and at a heat treatment temperature ofabout 80° C. to 200° C., depending on a material to be included in alayer and the structure of each layer to be formed.

The term “C₁-C₆₀ alkyl group” as used herein refers to a linear orbranched saturated aliphatic hydrocarbon monovalent group having 1 to 60carbon atoms, and non-limiting examples thereof include a methyl group,an ethyl group, a propyl group, an isobutyl group, a sec-butyl group, atert-butyl group, a pentyl group, an iso-amyl group, and a hexyl group.The term “C₁-C₆₀ alkylene group” as used herein refers to a divalentgroup having the same structure as the C₁-C₆₀ alkyl group.

The term “C₂-C₆₀ alkenyl group” as used herein refers to a hydrocarbongroup formed by substituting at least one carbon-carbon double bond inthe middle or at the terminus of the C₂-C₆₀ alkyl group, andnon-limiting examples thereof include an ethenyl group, a propenylgroup, and a butenyl group. The term “C₂-C₆₀ alkenylene group” as usedherein refers to a divalent group having the same structure as theC₂-C₆₀ alkenyl group.

The term “C₂-C₆₀ alkynyl group” as used herein refers to a hydrocarbongroup formed by substituting at least one carbon-carbon triple bond inthe middle or at the terminus of the C₂-C₆₀ alkyl group, andnon-limiting examples thereof include an ethynyl group and a propynylgroup. The term “C₂-C₆₀ alkynylene group” as used herein refers to adivalent group having the same structure as the C₂-C₆₀ alkynyl group.

The term “C₁-C₆₀ alkoxy group” as used herein refers to a monovalentgroup represented by —OA₁₀₁ (wherein A₁₀₁ is the C₁-C₆₀ alkyl group),and non-limiting examples thereof include a methoxy group, an ethoxygroup, and an isopropyloxy group.

The term “C₃-C₁₀ cycloalkyl group” as used herein refers to a monovalentsaturated hydrocarbon monocyclic group having 3 to 10 carbon atoms, andnon-limiting examples thereof include a cyclopropyl group, a cyclobutylgroup, a cyclopentyl group, a cyclohexyl group, and a cycloheptyl group.The term “C₃-C₁₀ cycloalkylene group” as used herein refers to adivalent group having the same structure as the C₃-C₁₀ cycloalkyl group.

The term “C₁₀-C₁₀ heterocycloalkyl group” as used herein refers to amonovalent saturated monocyclic group having at least one heteroatomselected from N, O, Si, P, and S as a ring-forming atom and 1 to 10carbon atoms, and non-limiting examples thereof include a1,2,3,4-oxatriazolidinyl group, a tetrahydrofuranyl group, and atetrahydrothiophenyl group. The term “C₁-C₁₀ heterocycloalkylene group”as used herein refers to a divalent group having the same structure asthe C₁-C₁₀ heterocycloalkyl group.

The term “C₃-C₁₀ cycloalkenyl group” as used herein refers to amonovalent monocyclic group that has 3 to 10 carbon atoms and at leastone carbon-carbon double bond in the ring thereof and does not havearomaticity, and non-limiting examples thereof include a cyclopentenylgroup, a cyclohexenyl group, and a cycloheptenyl group. The term “C₃-C₁₀cycloalkenylene group” as used herein refers to a divalent group havingthe same structure as the C₃-C₁₀ cycloalkenyl group.

The term “C₁-C₁₀ heterocycloalkenyl group” as used herein refers to amonovalent monocyclic group that has at least one heteroatom selectedfrom N, 0, Si, P, and S as a ring-forming atom, 1 to 10 carbon atoms,and at least one carbon-carbon double bond in its ring. Non-limitingexamples of the C₁-C₁₀ heterocycloalkenyl group include a4,5-dihydro-1,2,3,4-oxatriazolyl group, a 2,3-dihydrofuranyl group and a2,3-dihydrothiophenyl group. The term “C₁-C₁₀ heterocycloalkenylenegroup” as used herein refers to a divalent group having the samestructure as the C₁-C₁₀ heterocycloalkenyl group.

The term “C₆-C₆₀ aryl group” as used herein refers to a monovalent grouphaving a carbocyclic aromatic system having 6 to 60 carbon atoms, andthe term “C₆-C₆₀ arylene group” as used herein refers to a divalentgroup having a carbocyclic aromatic system having 6 to 60 carbon atoms.Non-limiting examples of the C₆-C₆₀ aryl group include a phenyl group, anaphthyl group, an anthracenyl group, a phenanthrenyl group, a pyrenylgroup, and a chrysenyl group. When the C₆-C₆₀ aryl group and the C₆-C₆₀arylene group each include two or more rings, the rings may be fused toeach other.

The term “C₁-C₆₀ heteroaryl group” as used herein refers to a monovalentgroup having a heterocyclic aromatic system that has at least oneheteroatom selected from N, O, Si, P, and S as a ring-forming atom, inaddition to 1 to 60 carbon atoms. The term “C₁-C₆₀ heteroarylene group”as used herein refers to a divalent group having a heterocyclic aromaticsystem that has at least one heteroatom selected from N, O, Si, P, and Sas a ring-forming atom, in addition to 1 to 60 carbon atoms.Non-limiting examples of the C₁-C₆₀ heteroaryl group include a pyridinylgroup, a pyrimidinyl group, a pyrazinyl group, a pyridazinyl group, atriazinyl group, a quinolinyl group, and an isoquinolinyl group. Whenthe C₁-C₆₀ heteroaryl group and the C₁-C₆₀ heteroarylene group eachinclude two or more rings, the rings may be fused to each other.

The term “C₆-C₆₀ aryloxy group” as used herein refers to —OA₁₀₂ (whereinA₁₀₂ is the C₆-C₆₀ aryl group), and a C₆-C₆₀ arylthio group used hereinindicates —SA₁₀₃ (wherein A₁₀₃ is the C₆-C₆₀ aryl group).

The term “monovalent non-aromatic condensed polycyclic group” as usedherein refers to a monovalent group (for example, having 8 to 60 carbonatoms) that has two or more rings condensed with each other, only carbonatoms as a ring-forming atom, and non-aromaticity in the entiremolecular structure. A detailed example of the monovalent non-aromaticcondensed polycyclic group is a fluorenyl group. The term “divalentnon-aromatic condensed polycyclic group,” used herein, refers to adivalent group having the same structure as the monovalent non-aromaticcondensed polycyclic group.

The term “monovalent non-aromatic condensed heteropolycyclic group” asused herein refers to a monovalent group (for example, having 1 to 60carbon atoms) that has two or more rings condensed to each other, has atleast one heteroatom selected from N, O, Si, P, and S, other than carbonatoms, as a ring-forming atom, and has non-aromaticity in the entiremolecular structure. An example of the monovalent non-aromatic condensedheteropolycyclic group is a carbazolyl group. The term “divalentnon-aromatic condensed heteropolycyclic group,” used herein, refers to adivalent group having the same structure as the monovalent non-aromaticcondensed heteropolycyclic group.

The term “C₅-C₆₀ carbocyclic group” as used herein refers to amonocyclic or polycyclic group having 5 to 60 carbon atoms in which aring-forming atom is a carbon atom only. The C₅-C₆₀ carbocyclic groupmay be an aromatic carbocyclic group or a non-aromatic carbocyclicgroup. The C₅-C₆₀ carbocyclic group may be a ring, such as a benzene, amonovalent group, such as a phenyl group, or a divalent group, such as aphenylene group. In one or more embodiments, depending on the number ofsubstituents connected to the C₅-C₆₀ carbocyclic group, the C₅-C₆₀carbocyclic group may be a trivalent group or a quadrivalent group.

The term “C₁-C₆₀ heterocyclic group” as used herein refers to a grouphaving the same structure as the C₁-C₆₀ carbocyclic group, except thatas a ring-forming atom, at least one heteroatom selected from N, O, Si,P, and S is used in addition to carbon (the number of carbon atoms maybe in a range of 1 to 60).

At least one substituent of the substituted C₅-C₆₀ carbocyclic group,substituted C₁-C₆₀ heterocyclic group, the substituted C₃-C₁₀cycloalkylene group, the substituted C₁-C₁₀ heterocycloalkylene group,the substituted C₃-C₁₀ cycloalkenylene group, the substituted C₁-C₁₀heterocycloalkenylene group, the substituted C₆-C₆₀ arylene group, thesubstituted C₁-C₆₀ heteroarylene group, the substituted divalentnon-aromatic condensed polycyclic group, the substituted divalentnon-aromatic condensed heteropolycyclic group, the substituted C₁-C₆₀alkyl group, the substituted C₂-C₆₀ alkenyl group, the substitutedC₂-C₆₀ alkynyl group, the substituted C₁-C₆₀ alkoxy group, thesubstituted C₃-C₁₀ cycloalkyl group, the substituted C₁-C₁₀heterocycloalkyl group, the substituted C₃-C₁₀ cycloalkenyl group, thesubstituted C₁-C₁₀ heterocycloalkenyl group, the substituted C₆-C₆₀ arylgroup, the substituted C₆-C₆₀ aryloxy group, the substituted C₆-C₆₀arylthio group, the substituted C₁-C₆₀ heteroaryl group, the substitutedmonovalent non-aromatic condensed polycyclic group, and the substitutedmonovalent non-aromatic condensed heteropolycyclic group may be selectedfrom:

deuterium (-D), —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, anitro group, an amidino group, a hydrazino group, a hydrazono group, aC₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, anda C₁-C₆₀ alkoxy group;

a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group,and a C₁-C₆₀ alkoxy group, each substituted with at least one selectedfrom deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, anitro group, an amidino group, a hydrazino group, a hydrazono group, aC₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,a monovalent non-aromatic condensed heteropolycyclic group,—Si(Q₁₁)(Q₁₂)(Q₁₃), —N(Q₁₁)(Q₁₂), —B(Q₁₁)(Q₁₂), —C(═O)(Q₁₁),—S(═O)₂(Q₁₁), and —P(═O)(Q₁₁)(Q₁₂);

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group;

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, amonovalent non-aromatic condensed polycyclic group, a monovalentnon-aromatic condensed heteropolycyclic group, —Si(Q₂₁)(Q₂₂)(Q₂₃),—N(Q₂₁)(Q₂₂), —B(Q₂₁)(Q₂₂), —C(═O)(Q₂₁), —S(═O)₂(Q₂₁), and—P(═O)(Q₂₁)(Q₂₂); and

—Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁),—S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂),

wherein Q₁₁ to Q_(13,) Q₂₁ to Q_(23,) and Q₃₁ to Q₃₃ may eachindependently be selected from hydrogen, deuterium, —F, —Cl, —Br, —I, ahydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,a monovalent non-aromatic condensed heteropolycyclic group, a biphenylgroup, and a terphenyl group.

The term “Ph”, as used herein, may refer to a phenyl group; the term“Me”, as used herein, may refer to a methyl group; the term “Et”, asused herein, may refer to an ethyl group; the terms “ter-Bu” or “But”,as used herein, may refer to a tert-butyl group; and the term “OMe” asused herein may refer to a methoxy group.

The term “biphenyl group” as used therein refers to “a phenyl groupsubstituted with a phenyl group.” For example, a “biphenyl group” is asubstituted phenyl group having a C₆-C₆₀ aryl group as a substituent.

The term “terphenyl group” as used herein refers to “a phenyl groupsubstituted with a biphenyl group.” For example, a “terphenyl group” isa substituted phenyl group having a C₆-C₆₀ aryl group substituted with aC₆-C₆₀ aryl group as a substituent.

* and *' used herein, unless defined otherwise, each refer to a bindingsite to a neighboring atom in a corresponding formula.

The term “or” is not an exclusive term. For example, a compositionincluding A or B would encompass a composition including A, acomposition including B, and a composition including A and B.

Hereinafter, a compound according to embodiments and an organiclight-emitting device according to embodiments will be described indetail with reference to Synthesis Examples and Examples. The wording “Bwas used instead of A” used in describing Synthesis Examples refers tothat an identical molar equivalent of B was used in place of A.

The following Examples and Comparative Examples are provided in order tohighlight characteristics of one or more embodiments, but it will beunderstood that the Examples and Comparative Examples are not to beconstrued as limiting the scope of the embodiments, nor are theComparative Examples to be construed as being outside the scope of theembodiments. Further, it will be understood that the embodiments are notlimited to the particular details described in the Examples andComparative Examples.

SYNTHESIS EXAMPLES

The structures of compounds used in the Synthesis Examples were asfollows:

Synthesis Example 1 Synthesis of Compound A-1

Synthesis of Intermediate Int-1

As a starting material, 1 equivalent of Compound S was dissolved in 100ml of ether and cooled to a temperature of −78° C. Then, 1.2 equivalentsof 1.6 M hex-methyllithium was added thereto and stirred for 1 hour.Then, the resulting mixture was gradually heated to ambient temperatureand stirred for 4 hours. After the reaction was completed, an extractionprocess was performed thereon by using 200 mL of water and an organiclayer was dried under reduced pressure. The result was recrystallizedwith a mixture of ethanol and acetone (volume ratio of 1:1), therebycompleting the preparation of Intermediate Int-1 (67%).

HRMS ([M]⁺) calcd for C₂₇H₂₂BrNO: 456.38, Found: 455

Calculated values through atom analysis of C₂₇H₂₂BrNO: C, 71.06; H,4.86; Br, 17.51; N, 3.07; 0, 3.51

Synthesis of Intermediate Int-2

Intermediate Int-1 was dissolved in 150 mL of strong H₃PO₄ and stirredfor 5.5 hours. An extraction process was performed thereon by using 200mL of water and 200 mL of ethyl acetate, and an organic layer was driedunder reduced pressure. The result was recrystallized with 150 mL ofethanol, thereby completing the preparation of Intermediate Int-2(72%).

HRMS ([M]⁺) calcd for C₂₇H₂₀BrN: 438.37, Found: 437

Synthesis of Compound A-1

1 equivalent of Intermediate Int-2 and 1.2 equivalents of Compound T-1were added to a flask, and 0.03 equivalents of Pd(dba)₃, 0.06equivalents of (t-Bu)₃P, and toluene (based on 0.1 M 1 eq. reagent) wereadded thereto. Then, the resulting mixture was refluxed and stirred for5 hours and cooled to ambient temperature. An extraction process wasperformed thereon by using methylene chloride and a washing process wasperformed thereon. The obtained material was dried with MgSO₄ anddistilled under reduced pressure. Then, the residue obtained therefromwas separated by a column, thereby completing the preparation ofCompound A-1(71.4%).

HRMS ([M]⁺) calcd for C₄₈H₃₄N₄: 666.83, Found: 665

Calculated values through atom analysis of C₄₈H₃₄N₄: C, 86.46; H, 5.14;N, 8.40

Synthesis Example 2 Synthesis of Compound A-2

1 equivalent of Intermediate Int-2, which was synthesized in the samemanner as in Synthesis Example 1, and 1.2 equivalent of Compound T-2were added to a flask, and 0.03 equivalents of Pd(dba)₃, 0.06equivalents of (t-Bu)₃P, and toluene (based on 0.1 M 1 eq. reagent) wereadded thereto. Then, the resulting mixture was refluxed and stirred for5 hours and cooled to ambient temperature. An extraction process wasperformed thereon by using methylene chloride and a washing process wasperformed thereon. The obtained material was dried with MgSO₄ anddistilled under reduced pressure. Then, the residue obtained therefromwas separated by a column, thereby completing the preparation ofCompound A-2(73.7%).

HRMS ([M]⁺) calcd for C₄₈H₃₄N₄: 666.83, Found: 665

Calculated values through atom analysis of C₄₈H₃₄N₄: C, 86.46; H, 5.14;N, 8.40

Synthesis Example 3 Synthesis of Compound A-10

1 equivalent of Intermediate Int-2, which was synthesized in the samemanner as in Synthesis Example 1, and 1.2 equivalent of Compound T-3were added to a flask, and 0.03 equivalents of Pd(dba)₃, 0.06equivalents of (t-Bu)₃P, and toluene (based on 0.1 M 1 eq. reagent) wereadded thereto. Then, the resulting mixture was refluxed and stirred for5 hours and cooled to ambient temperature. An extraction process wasperformed thereon by using methylene chloride and a washing process wasperformed thereon. The obtained material was dried with MgSO₄ anddistilled under reduced pressure. Then, the residue obtained therefromwas separated by a column, thereby completing the preparation ofCompound A-10 (75.9%).

HRMS ([M]⁺) calcd for C₅₂H₃₆N₄: 716.89, Found: 715

Calculated values through atom analysis of C₅₂H₃₆N₄: C, 87.12; H, 5.06;N, 7.82

Synthesis Example 4 Synthesis of Compound A-15

1 equivalent of Intermediate Int-2, which was synthesized in the samemanner as in Synthesis Example 1, and 1.2 equivalent of Compound T-4were added to a flask, and 0.03 equivalents of Pd(dba)₃, 0.06equivalents of (t-Bu)₃P, and toluene (based on 0.1 M 1 eq. reagent) wereadded thereto. Then, the resulting mixture was refluxed and stirred for5 hours and cooled to ambient temperature. An extraction process wasperformed thereon by using methylene chloride and a washing process wasperformed thereon. The obtained material was dried with MgSO₄ anddistilled under reduced pressure. Then, the residue obtained therefromwas separated by a column, thereby completing the preparation ofCompound A-15 (75.9%).

HRMS ([M]⁺) calcd for C₅₂H₃₆N₄: 716.89, Found: 715

Calculated values through atom analysis of C₅₂H₃₆N₄: C, 87.12; H, 5.06;N, 7.82

Synthesis Example 5 Synthesis of Compound A-32

Synthesis of Intermediate Int-4

As a starting material, Intermediate Int-3 and trifluoromethanesulfonicacid (CF₃SO₃H) were added to a flask and stirred at ambient temperaturefor 24 hours. Then, a water and pyridine mixed solvent (volume ratio of8:1) was added thereto and refluxed and stirred for 30 minutes. Then,the resulting mixture was cooled to ambient temperature, and anextraction process was performed thereon by using methylene chloride.The obtained material was dried by using MgSO₄ and distilled underreduced pressure. Then, the residue obtained therefrom was separated bya column, thereby completing the preparation of Intermediate Int-4(41%).

HRMS ([M]⁺) calcd for C₂₄H₁₄BrNO: 412.29, Found: 411

Synthesis of Compound A-32

1 equivalent of Intermediate Int-4 and 1.2 equivalents of Compound T-2were added to a flask, and 0.03 equivalents of Pd(dba)₃, 0.06equivalents of (t-Bu)₃P, and toluene (based on 0.1 M 1 eq. reagent) wereadded thereto. Then, the resulting mixture was refluxed and stirred for5 hours and cooled to ambient temperature. An extraction process wasperformed thereon by using methylene chloride and a washing process wasperformed thereon. The obtained material was dried with MgSO₄ anddistilled under reduced pressure. Then, the residue obtained therefromwas separated by a column, thereby completing the preparation ofCompound A-32(67%).

HRMS ([M]⁺) calcd for C₄₅H₂₈N₄O: 640.75, Found: 639

Calculated values through atom analysis of C₄₅H₂₈N₄O: C, 84.35; H, 4.40;N, 8.74; O, 2.50

Synthesis Example 6 Synthesis of Compound A-43

1 equivalent of Intermediate Int-4 and 1.2 equivalents of Compound T-3were added to a flask, and 0.03 equivalents of Pd(dba)₃, 0.06equivalents of (t-Bu)₃P, and toluene (based on 0.1 M 1 eq. reagent) wereadded thereto. Then, the resulting mixture was refluxed and stirred for5 hours and cooled to ambient temperature. An extraction process wasperformed thereon by using methylene chloride and a washing process wasperformed thereon. The obtained material was dried with MgSO₄ anddistilled under reduced pressure. Then, the residue obtained therefromwas separated by a column, thereby completing the preparation ofCompound A-43 (68%).

HRMS calcd for C₄₉H₃₀N₄O: 690.81, Found: 689

Calculated values through atom analysis of C₄₉H₃₀N₄O: C, 85.20; H, 4.38;N, 8.11; O, 2.32

Synthesis Example 7 Synthesis of Compound A-35

(1) Synthesis of Intermediate Int-6

As a starting material, Intermediate Int-5 and trifluoromethanesulfonicacid (CF₃SO₃H) were added to a flask and stirred at ambient temperaturefor 24 hours. Then, a water and pyridine mixed solvent (volume ratio of8:1) was added thereto and refluxed and stirred for 30 minutes. Then,the resulting mixture was cooled to ambient temperature, and anextraction process was performed thereon by using methylene chloride.The obtained material was dried by using MgSO₄ and distilled underreduced pressure. Then, the residue obtained therefrom was separated bya column, thereby completing the preparation of Intermediate Int-6(39.7%).

HRMS ([M]⁺) calcd for C₂₄H₁₄BrNS: 428.35, Found: 427

(2) Synthesis of Compound A-35

1 equivalent of Intermediate Int-6 and 1.2 equivalents of Compound T-2were added to a flask, and 0.03 equivalents of Pd(dba)₃, 0.06equivalents of (t-Bu)₃P, and toluene (based on 0.1 M 1 eq. reagent) wereadded thereto. Then, the resulting mixture was refluxed and stirred for5 hours and cooled to ambient temperature. An extraction process wasperformed thereon by using methylene chloride and a washing process wasperformed thereon. The obtained material was dried with MgSO₄ anddistilled under reduced pressure. Then, the residue obtained therefromwas separated by a column, thereby completing the preparation ofCompound A-35 (67%).

HRMS ([M]⁺) calcd for C₄₅H₂₈N₄S: 656.81, Found: 655

Calculated values through atom analysis of C₄₅H₂₈N₄S: C, 82.29; H, 4.30;N, 8.53; S, 4.88

Synthesis Example 8 Synthesis of Compound A-49

1 equivalent of Intermediate Int-6 and 1.2 equivalents of Compound T-3were added to a flask, and 0.03 equivalents of Pd(dba)₃, 0.06equivalents of (t-Bu)₃P, and toluene (based on 0.1 M 1 eq. reagent) wereadded thereto. Then, the resulting mixture was refluxed and stirred for5 hours and cooled to ambient temperature. An extraction process wasperformed thereon by using methylene chloride and a washing process wasperformed thereon. The obtained material was dried with MgSO₄ anddistilled under reduced pressure. Then, the residue obtained therefromwas separated by a column, thereby completing the preparation ofCompound A-49 (57%).

HRMS ([M]⁺) calcd for C₄₉H₃₀N₄S: 706.87, Found: 705

Calculated values through atom analysis of C₄₉H₃₀N₄S: C, 83.26; H, 4.28;N, 7.93; S, 4.54

EXAMPLE Example 1

A glass substrate, in which an ITO/Ag/ITO anode was formed, wasultrasonically cleaned by using isopropyl alcohol and pure water eachfor 5 minutes and then cleaned by exposure to UV irradiation for 10minutes and ozone. Then, the glass substrate was loaded into a vacuumdeposition apparatus.

2-TNATA was vacuum-deposited on the ITO/Ag/ITO anode to form a holeinjection layer having a thickness of 600 Å, and NPB wasvacuum-deposited on the hole injection layer to form a hole transportlayer having a thickness of 300 Å.

Bis-(1-phenylisoquinolyl)acetylacetonate iridium(III) (Ir(piq)₂(acac))and CBP were co-deposited on the hole transport layer at a weight ratioof 15:85 to form an emission layer having a thickness of 300 Å.

Compound A-1 was deposited on the emission layer to form an electrontransport layer having a thickness of 300 Å, and Al was deposited on theelectron transport layer to form a cathode having a thickness of 1,200Å, thereby completing the manufacture of an organic light-emittingdevice.

Examples 2 to 10 and Comparative Example 1 and 2

Organic light-emitting devices of Examples 2 to 10 and ComparativeExamples 1 and 2 were manufactured in the same manner as in Example 1,except that Compounds shown in Table 1 were each used instead ofCompound A-1 in forming an electron transport layer.

Evaluation Example 1

The efficiency and lifespan of the organic light-emitting devicesmanufactured according to Examples 1 to 10 and Comparative Examples 1and 2 were evaluated by using a Keithley SMU 236 and a luminance meterPR650, and results thereof are shown in Table 1. The lifespan (T₉₅)indicates an amount of time that lapsed when luminance was 95% ofinitial luminance (100%).

TABLE 1 Electron Efficiency Lifespan (T₉₅) transport layer (cd/A) (hr)(@3,700 nit) Example 1 A-1 51 923 Example 2 A-2 48.8 911 Example 3 A-1047.7 897 Example 4 A-15 47.9 921 Example 5 A-23 49.2 943 Example 6 A-2948.0 937 Example 7 A-32 47.9 956 Example 8 A-35 42 942 Example 9 A-4346.4 965 Example 10 A-49 42.7 970 Comparative Example 1 Alq3 38.4 789Comparative Example 2 HT-A 47.4 884

Referring to Table 1, it may be seen that the organic light-emittingdevices of Examples 1 to 10 had excellent lifespan characteristics,compared to those of Comparative Examples 1 and 2. Also, it may be seenthat the organic light-emitting devices of Examples 1 to 7 had excellentefficiency characteristics, compared to those of Comparative Examples 1and 2.

According to one or more example embodiments, an organic light-emittingdevice including the polycyclic compound may have a low driving voltage,high efficiency, high luminance, and a long lifespan.

Example embodiments have been disclosed herein, and although specificterms are employed, they are used and are to be interpreted in a genericand descriptive sense only and not for purpose of limitation. In someinstances, as would be apparent to one of ordinary skill in the art asof the filing of the present application, features, characteristics,and/or elements described in connection with a particular embodiment maybe used singly or in combination with features, characteristics, and/orelements described in connection with other embodiments unless otherwisespecifically indicated. Accordingly, it will be understood by those ofskill in the art that various changes in form and details may be madewithout departing from the spirit and scope of the present invention asset forth in the following claims.

What is claimed is:
 1. A polycyclic compound represented by Formula 1:

wherein, in Formula 1, X₁ is C(R₁₁)(R₁₂), N(R₁₃), O, or S, and R₁ to R₁₃are each independently a structure represented by Formula 2, hydrogen,deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, a substituted or unsubstituted C₁-C₆₀ alkyl group, a substitutedor unsubstituted C₂-C₆₀ alkenyl group, a substituted or unsubstitutedC₂-C₆₀ alkynyl group, a substituted or unsubstituted C₁-C₆₀ alkoxygroup, a substituted or unsubstituted C₃-C₁₀ cycloalkyl group, asubstituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, asubstituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted orunsubstituted C₁-C₁₀ heterocycloalkenyl group, a substituted orunsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₆-C₆₀aryloxy group, a substituted or unsubstituted C₆-C₆₀ arylthio group, asubstituted or unsubstituted C₁-C₆₀ heteroaryl group, a substituted orunsubstituted monovalent non-aromatic condensed polycyclic group, asubstituted or unsubstituted monovalent non-aromatic condensedheteropolycyclic group, —Si(Q₁)(Q₂)(Q₃), —N(Q₁)(Q₂), —B(Q₁)(Q₂),—C(═O)(Q₁), —S(═O)₂(Q₁), or —P(═O)(Q₁)(Q₂), at least one of R₁ to R₁₀having a structure represented by Formula 2,

wherein, in Formulae 1 and 2, L₁ is a substituted or unsubstitutedC₃-C₁₀ cycloalkylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkylene group, a substituted or unsubstituted C₃-C₁₀cycloalkenylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenylene group, a substituted or unsubstituted C₆-C₆₀arylene group, a substituted or unsubstituted C₁-C₆₀ heteroarylenegroup, a substituted or unsubstituted divalent non-aromatic condensedpolycyclic group, or a substituted or unsubstituted divalentnon-aromatic condensed heteropolycyclic group, Ar₁ is a substituted orunsubstituted C₁-C₆₀ heterocyclic group having at least one *—N═*′moiety, a1 is an integer from 1 to 5, b1 is an integer from 1 to 5, whena1 is two or more, two or more L₁(s) are identical to or different fromeach other, when b1 is two or more, two or more Ar₁(s) are identical toor different from each other, Ar₂ is a substituted or unsubstitutedC₆-C₆₀ aryl group, a substituted or unsubstituted C₆-C₆₀ aryloxy group,a substituted or unsubstituted C₆-C₆₀ arylthio group, or a substitutedor unsubstituted C₁-C₆₀ heteroaryl group, and R₁₃ and Ar₂ are separateor are linked to a neighboring substituent to form a substituted orunsubstituted ring, * and *′ each indicate a binding site to aneighboring atom, and at least one substituent of the substituted C₃-C₁₀cycloalkylene group, the substituted C₁-C₁₀ heterocycloalkylene group,the substituted C₃-C₁₀ cycloalkenylene group, the substituted C₁-C₁₀heterocycloalkenylene group, the substituted C₆-C₆₀ arylene group, thesubstituted C₁-C₆₀ heteroarylene group, the substituted divalentnon-aromatic condensed polycyclic group, the divalent non-aromaticcondensed heteropolycyclic group, the substituted C₁-C₆₀ alkyl group,the substituted C₂-C₆₀ alkenyl group, the substituted C₂-C₆₀ alkynylgroup, the substituted C₁-C₆₀ alkoxy group, the substituted C₃-C₁₀cycloalkyl group, the substituted C₁-C₁₀ heterocycloalkyl group, thesubstituted C₃-C₁₀ cycloalkenyl group, the substituted C₁-C₁₀heterocycloalkenyl group, the substituted C₆-C₆₀ aryl group, thesubstituted C₆-C₆₀ aryloxy group, the substituted C₆-C₆₀ arylthio group,the substituted C₁-C₆₀ heteroaryl group, the substituted monovalentnon-aromatic condensed polycyclic group, the substituted monovalentnon-aromatic condensed heteropolycyclic group, the substituted C₁-C₆₀heterocyclic group, or the substituted ring is: deuterium, —F, —Cl, —Br,—I, a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀ alkynyl group, or a C₁-C₆₀ alkoxy group; aC₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, anda C₁-C₆₀ alkoxy group, each substituted with at least one selected fromdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₃-C₁₀cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, amonovalent non-aromatic condensed polycyclic group, a monovalentnon-aromatic condensed heteropolycyclic group, a C₁-C₆₀ heterocyclicgroup, —Si(Q₁₁)(Q₁₂)(Q₁₃), —N(Q₁₁)(Q₁₂), —B(Q₁₁)(Q₁₂), —C(═O)(Q₁₁),—S(═O)₂(Q₁₁), or —P(═O)(Q₁₁)(Q₁₂); a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, a C₁-C₆₀ heterocyclic group, abiphenyl group, or a terphenyl group; a C₃-C₁₀ cycloalkyl group, aC₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, a C₁-C₆₀ heterocyclic group, abiphenyl group, and a terphenyl group, each substituted with at leastone selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amidino group, a hydrazino group, a hydrazonogroup, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynylgroup, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, a biphenyl group, a terphenyl group,—Si(Q₂₁)(Q₂₂)(Q₂₃), —N(Q₂₁)(Q₂₂), —B(Q₂₁)(Q₂₂), —C(═O)(Q₂₁),—S(═O)₂(Q₂₁), or —P(═O)(Q₂₁)(Q₂₂); or —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂),—B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁), —S(═O)₂(Q₃₁), or —P(═O)(Q₃₁)(Q₃₂), wherein Q₁to Q₃, Q ₁₁ to Q₁₃, Q₂₁ to Q_(23,) and Q₃₁ to Q₃₃ are each independentlyhydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, an amidino group, a hydrazino group, a hydrazono group, aC₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, aC₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C ₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryl groupsubstituted with a C₁-C₆₀ alkyl group, a C₁-C₆₀ heteroaryl group, amonovalent non-aromatic condensed polycyclic group, a monovalentnon-aromatic condensed heteropolycyclic group, a C₁-C₆₀ heterocyclicgroup, a biphenyl group, or a terphenyl group.
 2. The polycycliccompound as claimed in claim 1, wherein L₁ is: a phenylene group, apentalenylene group, an indenylene group, a naphthylene group, anazulenylene group, a heptalenylene group, an indacenylene group, anacenaphthylene group, a fluorenylene group, a spiro-bifluorenylenegroup, a spiro-fluorene-benzofluorenylene group, a benzofluorenylenegroup, a dibenzofluorenylene group, a phenalenylene group, aphenanthrenylene group, an anthracenylene group, a fluoranthenylenegroup, a triphenylenylene group, a pyrenylene group, a chrysenylenegroup, a naphthacenylene group, a picenylene group, a perylenylenegroup, a pentaphenylene group, a hexacenylene group, a pentacenylenegroup, a rubicenylene group, a coronenylene group, an ovalenylene group,a pyrrolylene group, a thiophenylene group, a furanylene group, animidazolylene group, a pyrazolylene group, a thiazolylene group, anisothiazolylene group, an oxazolylene group, an isoxazolylene group, apyridinylene group, a pyrazinylene group, a pyrimidinylene group, apyridazinylene group, an isoindolylene group, an indolylene group, anindazolylene group, a purinylene group, a quinolinylene group, anisoquinolinylene group, a benzoquinolinylene group, a phthalazinylenegroup, a naphthyridinylene group, a quinoxalinylene group, aquinazolinylene group, a cinnolinylene group, a carbazolylene group, aphenanthridinylene group, an acridinylene group, a phenanthrolinylenegroup, a phenazinylene group, a benzimidazolylene group, abenzofuranylene group, a benzothiophenylene group, anisobenzothiazolylene group, a benzoxazolylene group, anisobenzoxazolylene group, a triazolylene group, a tetrazolylene group,an oxadiazolylene group, a triazinylene group, a dibenzofuranylenegroup, a dibenzothiophenylene group, a dibenzosilolylene group, abenzocarbazolylene group, a dibenzocarbazolylene group, athiadiazolylene group, an imidazopyridinylene group, or animidazopyrimidinylene group; or a phenylene group, a pentalenylenegroup, an indenylene group, a naphthylene group, an azulenylene group, aheptalenylene group, an indacenylene group, an acenaphthylene group, afluorenylene group, a spiro-bifluorenylene group, aspiro-fluorene-benzofluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenalenylene group, a phenanthrenylenegroup, an anthracenylene group, a fluoranthenylene group, atriphenylenylene group, a pyrenylene group, a chrysenylene group, anaphthacenylene group, a picenylene group, a perylenylene group, apentaphenylene group, a hexacenylene group, a pentacenylene group, arubicenylene group, a coronenylene group, an ovalenylene group, apyrrolylene group, a thiophenylene group, a furanylene group, animidazolylene group, a pyrazolylene group, a thiazolylene group, anisothiazolylene group, an oxazolylene group, an isoxazolylene group, apyridinylene group, a pyrazinylene group, a pyrimidinylene group, apyridazinylene group, an isoindolylene group, an indolylene group, anindazolylene group, a purinylene group, a quinolinylene group, anisoquinolinylene group, a benzoquinolinylene group, a phthalazinylenegroup, a naphthyridinylene group, a quinoxalinylene group, aquinazolinylene group, a cinnolinylene group, a carbazolylene group, aphenanthridinylene group, an acridinylene group, a phenanthrolinylenegroup, a phenazinylene group, a benzimidazolylene group, abenzofuranylene group, a benzothiophenylene group, anisobenzothiazolylene group, a benzoxazolylene group, anisobenzoxazolylene group, a triazolylene group, a tetrazolylene group,an oxadiazolylene group, a triazinylene group, a dibenzofuranylenegroup; a dibenzothiophenylene group, a dibenzosilolylene group, abenzocarbazolylene group, a dibenzocarbazolylene group, athiadiazolylene group, an imidazopyridinylene group, or animidazopyrimidinylene group, each substituted with deuterium, —F, —Cl,—Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidinogroup, a hydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, aC₁-C₂₀ alkoxy group, a cyclopentyl group, a cyclohexyl group, acycloheptyl group, a cyclopentenyl group, a cyclohexenyl group, a phenylgroup, a biphenyl group, a terphenyl group, a pentalenyl group, anindenyl group, a naphthyl group, an azulenyl group, a heptalenyl group,an indacenyl group, an acenaphthyl group, a fluorenyl group, aspiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenylgroup, a phenalenyl group, a phenanthrenyl group, an anthracenyl group,a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, achrysenyl group, a naphthacenyl group, a picenyl group, a perylenylgroup, a pentaphenyl group, a hexacenyl group, a pentacenyl group, arubicenyl group, a coronenyl group, an ovalenyl group, a pyrrolyl group,a thiophenyl group, a furanyl group, an imidazolyl group, a pyrazolylgroup, a thiazolyl group, an isothiazolyl group, an oxazolyl group, anisoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinylgroup, a pyridazinyl group, an isoindolyl group, an indolyl group, anindazolyl group, a purinyl group, a quinolinyl group, an isoquinolinylgroup, a benzoquinolinyl group, a phthalazinyl group, a naphthyridinylgroup, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, acarbazolyl group, a phenanthridinyl group, an acridinyl group, aphenanthrolinyl group, a phenazinyl group, a benzimidazolyl group, abenzofuranyl group, a benzothiophenyl group, an isobenzothiazolyl group,a benzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, atetrazolyl group, an oxadiazolyl group, a triazinyl group, adibenzofuranyl group, a dibenzothiophenyl group, a dibenzosilolylenegroup, a benzocarbazolyl group, a dibenzocarbazolyl group, athiadiazolyl group, an imidazopyridinyl group, an imidazopyrimidinylgroup, —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁),—S(═O)₂(Q₃₁), or —P(═O)(Q₃₁)(Q₃₂), wherein Q₃₁ to Q₃ are eachindependently a C₁-C₁₀ alkyl group, a C₁-C₁₀ alkoxy group, a phenylgroup, a phenyl group substituted with a C₁-C₁₀ alkyl group, a biphenylgroup, a terphenyl group, a naphthyl group, or a dibenzofuranyl group.3. The polycyclic compound as claimed in claim 1, wherein L₁ is a grouprepresented by one of Formula 3-1 to 3-49:

wherein, in Formulae 3-1 to 3-49, Y₁ is O, S, C(Z₃)(Z₄), N(Z₅), orSi(Z₆)(Z₇), Z₁ to Z₇ are each independently hydrogen, deuterium, —F,—Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an aminogroup, an amidino group, a hydrazine group, a hydrazone group, acarboxylic acid group or a salt thereof, a sulfonic acid group or a saltthereof, a phosphoric acid group or a salt thereof, a C₁-C₂₀ alkylgroup, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, a naphthyl group, a fluorenyl group, aspiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenylgroup, a phenanthrenyl group, an anthracenyl group, a pyrenyl group, achrysenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinylgroup, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group,a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, adibenzofuranyl group, a dibenzothiophenyl group, a triazinyl group, abenzimidazolyl group, a phenanthrolinyl group, or —Si(Q₃₃)(Q₃₄)(Q₃₅),wherein Q₃ to Q₃₅ are each independently a C₁-C₁₀ alkyl group, a C₁-C₁₀alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, or anaphthyl group, d2 is an integer from 0 to 2, d3 is an integer from 0 to3, d4 is an integer from 0 to 4, d5 is an integer from 0 to 5, d6 is aninteger from 0 to 6, d8 is an integer from 0 to 8, and * and *′ eachindicate a binding site to a neighboring atom.
 4. The polycycliccompound as claimed in claim 1, wherein L₁ is a group represented by oneof Formula 4-1 to 4-6:

wherein * and *' in Formulae 4-1 to 4-6 each indicate a binding site toa neighboring atom.
 5. The polycyclic compound as claimed in claim 1,wherein: X₁ is C(R₁₁)(R₁₂), and R₁₁ and R₁₂ are each independently: amethyl group, an ethyl group, a propyl group, an isobutyl group, asec-butyl group, a ter-butyl group, a pentyl group, an iso-amyl group,or a hexyl group; or a methyl group, an ethyl group, a propyl group, anisobutyl group, a sec-butyl group, a ter-butyl group, a pentyl group, aniso-amyl group, or a hexyl group, each substituted with deuterium, —F,—Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an aminogroup, a C₁-C₆₀ alkyl group, a C₆-C₆₀ aryl group, or a C₂-C₆₀ heteroarylgroup.
 6. The polycyclic compound as claimed in claim 1, wherein: X₁ isN(R₁₃), and Ar₂ and R₁₃ are each independently: a phenyl group, abiphenyl group, a terphenyl group, a naphthyl group, a phenanthrenylgroup, an anthracenyl group, a fluoranthenyl group, a triphenylenylgroup, or a pyrenyl group; a phenyl group, a biphenyl group, a terphenylgroup, a naphthyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, or a pyrenyl group, eachsubstituted with deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amino group, an amidino group, a hydrazinegroup, a hydrazone group, a carboxylic acid group or a salt thereof, asulfonic acid group or a salt thereof, a phosphoric acid group or a saltthereof, a C₁-C₂₀ alkyl group, or a C₁-C₂₀ alkoxy group, or Ar₂ and R₁₃are linked to a neighboring substituent to foim a substituted orunsubstituted benzene; a substituted or unsubstituted naphthalene; asubstituted or unsubstituted fluorene, a substituted or unsubstitutedspiro-fluorene, a substituted or unsubstituted pyridine, a substitutedor unsubstituted pyrazine, a substituted or unsubstituted pyrimidine, asubstituted or unsubstituted pyridazine, a substituted or unsubstitutedquinoline, a substituted or unsubstituted isoquinoline, a substituted orunsubstituted quinoxaline, a substituted or unsubstituted quinazoline,or a substituted or unsubstituted triazine, and at least one substituentof the substituted benzene, the substituted naphthalene, the substitutedfluorene, the substituted spiro-fluorene, the substituted pyridine, thesubstituted pyrazine, the substituted pyrimidine, the substitutedpyridazine, the substituted quinoline, the substituted isoquinoline, thesubstituted quinoxaline, the substituted quinazoline, and thesubstituted triazine is deuterium, —F, —Cl, —Br, —I, a cyano group, or aC₁-C₆₀ alkyl group.
 7. The polycyclic compound as claimed in claim 1,wherein: X₁ is N(R₁₃), and the compound represented by Formula 1 isrepresented by Formula 11 or 12:

wherein, in Formulae 11 and 12, R₁ to R₁₀ are defined the same as R₁ toR₁₀ of Formula 1, ring A₁ is a substituted or unsubstituted benzenegroup, a substituted or unsubstituted naphthalene group, a substitutedor unsubstituted fluorene group, a substituted or unsubstitutedspiro-fluorene group, a substituted or unsubstituted indene group, asubstituted or unsubstituted pyrrole group, a substituted orunsubstituted thiophene group, a substituted or unsubstituted furangroup, a substituted or unsubstituted imidazole group, a substituted orunsubstituted pyrazole group, a substituted or unsubstituted thiazolegroup, a substituted or unsubstituted isothiazole group, a substitutedor unsubstituted oxazole group, a substituted or unsubstituted isoxazolegroup, a substituted or unsubstituted pyridine group, a substituted orunsubstituted pyrazine group, a substituted or unsubstituted pyrimidinegroup, a substituted or unsubstituted pyridazine group, a substituted orunsubstituted quinoline group, a substituted or unsubstitutedisoquinoline group, a substituted or unsubstituted benzoquinoline group,a substituted or unsubstituted quinoxaline group, a substituted orunsubstituted quinazoline group, a substituted or unsubstitutedcarbazole group, a substituted or unsubstituted benzimidazole group, asubstituted or unsubstituted benzofuran group, a substituted orunsubstituted benzothiophene group, a substituted or unsubstitutedisobenzothiophene group, a substituted or unsubstituted benzoxazolegroup, a substituted or unsubstituted isobenzoxazole group, asubstituted or unsubstituted triazole group, a substituted orunsubstituted oxadiazole group, a substituted or unsubstituted triazinegroup, a substituted or unsubstituted dibenzofuran group, or asubstituted or unsubstituted dibenzothiophene group, R₂₁ and R₂₂ areeach independently hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxylgroup, a cyano group, a nitro group, a substituted or unsubstitutedC₁-C₆₀ alkyl group, a substituted or unsubstituted C₂-C₆₀ alkenyl group,a substituted or unsubstituted C₂-C₆₀ alkynyl group, a substituted orunsubstituted C₁-C₆₀ alkoxy group, a substituted or unsubstituted C₃-C₁₀cycloalkyl group, a substituted or unsubstituted C₁-C₁₀ heterocycloalkylgroup, a substituted or unsubstituted C₃-C₁₀ cycloalkenyl group, asubstituted or unsubstituted C₁-C₁₀ heterocycloalkenyl group, asubstituted or unsubstituted C₆-C₆₀ aryl group, a substituted orunsubstituted C₆-C₆₀ aryloxy group, a substituted or unsubstitutedC₆-C₆₀ arylthio group, a substituted or unsubstituted C₁-C₆₀ heteroarylgroup, a substituted or unsubstituted monovalent non-aromatic condensedpolycyclic group, or a substituted or unsubstituted monovalentnon-aromatic condensed heteropolycyclic group, at least one substituentof the substituted benzene group, the substituted naphthalene group, thesubstituted fluorene group, the substituted spiro-fluorene group, thesubstituted indene group, the substituted pyrrole group, the substitutedthiophene group, the substituted furan group, the substituted imidazolegroup, the substituted pyrazole group, the substituted thiazole group,the substituted isothiazole group, the substituted oxazole group, thesubstituted isoxazole group, the substituted pyridine group, thesubstituted pyrazine group, the substituted pyrimidine group, thesubstituted pyridazine group, the substituted quinoline group, thesubstituted isoquinoline group, the substituted benzoquinoline group,the substituted quinoxaline group, the substituted quinazoline group,the substituted carbazole group, the substituted benzimidazole group,the substituted benzofuran group, the substituted benzothiophene group,the substituted isobenzothiophene group, the substituted benzoxazolegroup, the substituted isobenzoxazole group, the substituted triazolegroup, the substituted oxadiazole group, the substituted triazine group,the substituted dibenzofuran group, the substituted dibenzothiophenegroup, the substituted 0-C₆₀ alkyl group, the substituted C₂-C₆₀ alkenylgroup, the substituted C₂-C₆₀ alkynyl group, the substituted C₁-C₆₀alkoxy group, the substituted C₃-C₁₀ cycloalkyl group, the substitutedC₁-C₁₀ heterocycloalkyl group, the substituted C₃-C₁₀ cycloalkenylgroup, the substituted C₁-C₁₀ heterocycloalkenyl group, the substitutedC₆-C₆₀ aryl group, the substituted C₆-C₆₀ aryloxy group, the substitutedC₆-C₆₀ arylthio group, the substituted C₁-C₆₀ heteroaryl group, thesubstituted monovalent non-aromatic condensed polycyclic group, or thesubstituted monovalent non-aromatic condensed heteropolycyclic group is:deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₆₀alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, or a C₁-C₆₀alkoxy group; or a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkylgroup, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, aC₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, aC₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclicgroup, a monovalent non-aromatic condensed heteropolycyclic group, abiphenyl group, or a terphenyl group.
 8. The polycyclic compound asclaimed in claim 7, wherein: the compound is represented by Formula 11,and the compound represented by Formula 11 is represented by Formula11-1:

wherein, in Formula 11-1, R₁ to R₁₀ are defined the same as R₁ to R₁₀ ofFormula 1, R₂₃ is hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxylgroup, a cyano group, a nitro group, a substituted or unsubstitutedC₁-C₆₀ alkyl group, a substituted or unsubstituted C₂-C₆₀ alkenyl group,a substituted or unsubstituted C₂-C₆₀ alkynyl group, a substituted orunsubstituted C₁-C₆₀ alkoxy group, a substituted or unsubstituted C₃-C₁₀cycloalkyl group, a substituted or unsubstituted C₁-C₁₀ heterocycloalkylgroup, a substituted or unsubstituted C₃-C₁₀ cycloalkenyl group, asubstituted or unsubstituted C₁-C₁₀ heterocycloalkenyl group, asubstituted or unsubstituted C₆-C₆₀ aryl group, a substituted orunsubstituted C₆-C₆₀ aryloxy group, a substituted or unsubstitutedC₆-C₆₀ arylthio group, a substituted or unsubstituted C₁-C₆₀ heteroarylgroup, a substituted or unsubstituted monovalent non-aromatic condensedpolycyclic group, or a substituted or unsubstituted monovalentnon-aromatic condensed heteropolycyclic group, r1 is an integer from 0to 4, when r1 is two or more, two or more R₂₃(s) are identical to ordifferent from each other and two or more neighboring R₂₃(s) areseparate or are linked to form a substituted or unsubstituted ring, atleast one substituent of the substituted C₁-C₆₀ alkyl group, thesubstituted C₂-C₆₀ alkenyl group, the substituted C₂-C₆₀ alkynyl group,the substituted C₁-C₆₀ alkoxy group, the substituted C₃-C₁₀ cycloalkylgroup, the substituted C₁-C₁₀ heterocycloalkyl group, the substitutedC₃-C₁₀ cycloalkenyl group, the substituted C₁-C₁₀ heterocycloalkenylgroup, the substituted C₆-C₆₀ aryl group, the substituted C₆-C₆₀ aryloxygroup, the substituted C₆-C₆₀ arylthio group, the substituted C₁-C₆₀heteroaryl group, the substituted monovalent non-aromatic condensedpolycyclic group, the substituted monovalent non-aromatic condensedheteropolycyclic group, or the substituted ring is: deuterium, —F, —Cl,—Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidinogroup, a hydrazino group, a hydrazono group, a C₁-C₆₀ alkyl group, aC₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, or a C₁-C₆₀ alkoxy group;or a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C ₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,a monovalent non-aromatic condensed heteropolycyclic group, a biphenylgroup, or a terphenyl group.
 9. The polycyclic compound as claimed inclaim 1, wherein Ar₂ is: a phenyl group, a biphenyl group, a terphenylgroup, a naphthyl group, a fluorenyl group, a spiro-bifluorenyl group, aspiro-fluorene-benzofluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, atriphenylenyl group, a pyrenyl group, or a chrysenyl group; or a phenylgroup, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a Spiro-bifluorenyl group, aspiro-fluorene-benzofluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, atriphenylenyl group, a pyrenyl group, or a chrysenyl group, eachsubstituted with deuterium, —F, -C1, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amidino group, a hydrazino group, a hydrazonogroup, a C₁-C₁₀ alkyl group, a C₁-C₁₀ alkoxy group, a phenyl group, abiphenyl group, a terphenyl group, a naphthyl group, a fluorenyl group,a spiro-bifluorenyl group, a spiro-fluorene-benzofluorenyl group, abenzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group,an anthracenyl group, a triphenylenyl group, a pyrenyl group, or achrysenyl group.
 10. The polycyclic compound as claimed in claim 1,wherein Ar₂ is a group represented by one of Formula 5-1 to 5-52:

wherein, in Formulae 5-1 to 5-52, Z₃₁ to Z₃₅ are each independentlyhydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, an amidino group, a hydrazino group, a hydrazono group, aC₁-C₂₀ alkyl group, a C₁-C₂₀ alkenyl group, a C₁-C₂₀ alkynyl group, aC₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, a terphenylgroup, a naphthyl group, a fluorenyl group, a spiro-bifluorenyl group, abenzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group,an anthracenyl group, a pyrenyl group, a chrysenyl group, a pyridinylgroup, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, aquinolinyl group, an isoquinolinyl group, a quinoxalinyl group, aquinazolinyl group, a carbazolyl group, a triazinyl group,—Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁),—S(═O)₂(Q₃₁), or —P(═O)(Q₃₁)(Q₃₂), wherein Q₁ to Q₃ and Q₃₁ to Q₃₃ areeach independently a C₁-C₁₀ alkyl group, a C₁-C₁₀ alkoxy group, a phenylgroup, a phenyl group substituted with a C₁-C₁₀ alkyl group, a biphenylgroup, a terphenyl group, a naphthyl group, or a dibenzofuranyl group,e2 is 1 or 2, e3 is an integer from 1 to 3, e4 is an integer from 1 to4, e5 is an integer from 1 to 5, e6 is an integer from 1 to 6, e7 is aninteger from 1 to 7, e9 is an integer from 1 to 9, and * indicates abinding site to a neighboring atom.
 11. The polycyclic compound asclaimed in claim 1, wherein Ar₁ is: an imidazolyl group, a pyrazolegroup, a thiazolyl group, an isothiazolyl group, an oxazolyl group, anisoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinylgroup, a pyridazinyl group, an indazolyl group, a purinyl group, aquinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, aphthalazinyl group, a naphthyridinyl group, a quinoxalinyl group, aquinazolinyl group, a cinnolinyl group, a phenanthridinyl group, anacridinyl group, a phenanthrolinyl group, a phenazinyl group, abenzimidazolyl group, an isobenzothiazolyl group, a benzoxazolyl group,an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group, anoxadiazolyl group, a triazinyl group, a thiadiazolyl group, animidazopyridinyl group, an imidazopyrimidinyl group, or an azacarbazolylgroup; or an imidazolyl group, a pyrazole group, a thiazolyl group, anisothiazolyl group, an oxazolyl group, an isoxazolyl group, a pyridinylgroup, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, anindazolyl group, a purinyl group, a quinolinyl group, an isoquinolinylgroup, a benzoquinolinyl group, a phthalazinyl group, a naphthyridinylgroup, a quinoxalinyl group, a quinazolinyl group, a cinnolinyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, aphenazinyl group, a benzimidazolyl group, an isobenzothiazolyl group, abenzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, atetrazolyl group, an oxadiazolyl group, a triazinyl group, athiadiazolyl group, an imidazopyridinyl group, an imidazopyrimidinylgroup, or an azacarbazolyl group, each substituted with deuterium, —F,—Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidinogroup, a hydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, or aC₁-C₂₀ alkoxy group.
 12. The polycyclic compound as claimed in claim 1,wherein Ar₁ is a group represented by one of Formula 7-1 to 7-59:

wherein, in Formulae 7-1 to 7-59, Z₅₁ and Z₅₂ are each independentlyhydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, an amidino group, a hydrazino group, a hydrazono group, aC₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, an imidazolyl group, apyrazole group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a pyridinyl group, a pyrazinyl group, apyrimidinyl group, a pyridazinyl group, an indazolyl group, a purinylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a phthalazinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a cinnolinyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolylgroup, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group,an oxadiazolyl group, a triazinyl group, a thiadiazolyl group, animidazopyridinyl group, an imidazopyrimidinyl group, or an azacarbazolylgroup, g2 is an integer from 0 to 2, g3 is an integer from 0 to 3, g4 isan integer from 0 to 4, g5 is an integer from 0 to 5, g6 is an integerfrom 0 to 6, and * and *′ each indicate a binding site to a neighboringatom.
 13. The polycyclic compound as claimed in claim 1, wherein thecompound represented by Formula 1 is represented by one of Formula 21 to24:

wherein, in Formulae 21 to 24, X₁, L₁, Ar₁, Ar₂, R₁ to R₁₀, a1, and b1are defined the same as X₁, L₁, Ar₁, Ar₂, R₁ to R₁₀, a1, and b1 ofFormula
 1. 14. The polycyclic compound as claimed in claim 1, whereinthe polycyclic compound is one of Compound A-1 to A-51:


15. An organic light-emitting device, comprising: a first electrode; asecond electrode facing the first electrode; and an organic layerbetween the first electrode and the second electrode, the organic layerincluding an emission layer, wherein the organic layer includes thepolycyclic compound as claimed in claim
 1. 16. The organiclight-emitting device as claimed in claim 15, wherein: the firstelectrode is an anode, the second electrode is a cathode, and theorganic layer further includes: a hole transport region between thefirst electrode and the emission layer, and an electron transport regionbetween the emission layer and the second electrode, the hole transportregion includes a hole injection layer, a hole transport layer, a bufferlayer, an emission auxiliary layer, or an electron blocking layer, andthe electron transport region includes a hole blocking layer, anelectron transport layer, or an electron injection layer.
 17. Theorganic light-emitting device as claimed in claim 16, wherein theelectron transport region includes the polycyclic compound.
 18. Theorganic light-emitting device as claimed in claim 17, wherein: theelectron transport region includes an electron transport layer and anelectron injection layer, and the electron transport layer or theelectron injection layer includes the polycyclic compound.
 19. Theorganic light-emitting device as claimed in claim 18, wherein theelectron transport layer or the electron injection layer furtherincludes an alkali metal, an alkaline earth metal, a rare-earth metal,an alkali metal compound, an alkaline earth-metal compound, a rare-earthmetal compound, an alkali metal complex, an alkaline earth-metalcomplex, or a rare-earth metal complex.
 20. The organic light-emittingdevice as claimed in claim 15, wherein: the emission layer includes adopant and a host, and the host includes an anthracene-based compound, apyrene-based compound, or a spiro-bifluorene-based compound.